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LIBRARY OF CONGRESS 




ODDEDSESbHE 



lUBRARY OF CONGRESS J 

/ 1T3~7 t 

f""^ pm^t |a j 



I UNITED STATES OF AliERICA. 



WRINKLES 



AND 



RECIPES, 



COMPILED FROM THE 



Scientific American. 



A Collection of Practical Suggestions, Processes, and Directions lor 

THE MECHANIC, 

THE ENGINEER, 

THE FARMER, and 

THE HOUSEKEEPER. 



II^I^ CrjSTIli^.TJBI>, 



EDITED BY 



R Revisers and ContrlMors: 



Professor R. H. THURSTON, C.E. 

Professor P. H. VANDER WEYDE, M.D. 

RICHARD H. BUEL, Mechanical Engineer. 

JOSHUA ROSE, Mechanical Engineer 



MO 

New-York : V^'^-T^^I^: 



3r Fai?k I^o^7^. 



// 



Entered according to Act of Congress, in the year 1875, by 

H. N. MUNN AND PARK BENJAMIN, 
in the Office of the Librarian of Congress, at Washington. 



If any luorher in the great army of those in 
whose intelligent labor lies the surest foundation 
for the prosperity of its all, finds among the sug- 
gestions here compiled one thought, as it is hoped 
he inay many, which shall lighten his toil or 
aid hinv in the production of better ivorh, then 
the editor sincerely trusts that that luorher will 
deem this little volume as prepared for his es- 
pecial benefit, and to him especially dedicated. 



PREFACE. 



The aim in tlie following pages lias been to compile a collec- 
tion of suggestions for the every-day use of the working-man, in 
his shop, about his dwelling, or in his household. The book is not 
an encyclopsedia of recipes, nor does it make any pretensions to 
that title ; on the contrary, a very large number of formulae have 
purposely been omitted, because they are, for the most part, at- 
tainable in other and more extensive works. Preference has been 
given to practical hints, and, while the majority of these have 
been carefully gathered and condensed from the back files of the 
Scientific American, and more especially from the letters of cor- 
respondents of that paper, a goodly proportion are entirely new 
and fresh, and have been prepared expressly for this book. 

For the contribution of a large part of the matter in, and for 
the general supervision of the department of Mechanics, the edi- 
tor is indebted to that thorough workman, Mr. Joshua Rose. To 
Mr. Richard H. Buel (whose articles are signed " B.") similar ac- 
knowledgments are owing for valuable papers on boilers, engines, 
and other topics in the department of Engineering. The general 
revision of the last-mentioned department has been the labor of 
Professor R. H. Thurston, of the Stevens Institute, as has the si- 
milar overlooking of the department of Technology, that of Pro- 
fessor P. H. Van der Weyde. To both of these distinguished 
gentlemen, as well as to Messrs. Munn & Co., the publishers of 
the Scientific American, who have most kindly afforded the facili- 
ties for the preparation of this work, the cordial acknowledgments 
of the editor are due. 

New- York, Nov. 1, 1875. 



CONTEIsTTS 



*^* Subjects will he found arranged alphahetically under the 
below-indexed subheadings of the 'carious departments. 



Mechanics: page 

Master Tools and their Uses 7 

Tools 16 

Mechanical Shop Wrinkles and Directions 38 

Engineeking: . 

Testing Materials 55 

The Engine and its Appendages 57 

The Boiler and its Attachments 87 

Belts, Pulleys, and Shafting 109 

Practical Technology : 

Cements, Glues, and Moulding Compositions 135 

Metal- Working Hints and Recipes 140 

Simple Instruments and their Uses 150 

Recipes for the Preparation of wood 156 

The Preservation and Preparation of Natural History 

Specimens 158 

Painting, Gilding, and Varnishing Recipes 166 

Hints about Drawing and Sketching 171 

Simple Galvanic Batteries and Electroplating Recipes 178 

Useful Chemical Recipes for Detection of Adulterations, 

etc 181 

The Farm : 

Farm Buildings 18D 

The Dairy 202 

Farm Hints and Recipes 204 

Household Hints 22;^ 



MECHANICS. 



MASTER-TOOLS: THEIR MANUFACTURE AND 

USE. 

The master-tools, here illustrated and described, comprise all 
that are necessary for plain machine- work in every description of 
metal ; and if they are made of the precise shape, and according 
to the given instructions, they will perform the full amount of 
duty here allotted to them, which, though it may appear to be 
unusually great, may be thoroughly relied upon for metal of any 
ordinary degree of hardness. Nor can any less amount of duty 
be obtained from them without evidencing inferior mechanical 
skill either in making or using the tool. It is true economy to ob- 
tain from a cutting tool its utmost amount of duty, which, though 
it may entail a little more drawing out and grinding of the tool 
in a given time, does not involve anymore as compared to the 
quantity of work performed. It is well within the mark to say 
that at least one third more duty, in a given* time, may be ob- 
tained from cutting-tools for metals (used in all machines having 
variable speeds and feeds, such as the lathe and the shaping- 
machine), than is obtained in the usual practice of our machine- 
shops, especially in the larger ones. 

Boring-tool for Brass. — The boring tool for brass-work, 
here shown, is a standard tool for either roughing out or finish- 




BORTNG-TOOL FOR BRASS. 



ing, both of which duties it will perform equally well. It is bent 
further round at the end than is the boring-tool for wrought-iron, 
to prevent it from jarring or chattering. It is a master-tool in 
every sense of the word. It should be hardened right out, and 
used with a quick speed and light feed, no matter how deep the 



8 



MECHANICS. 



cut is. To prevent chattering or jarring when extending far out 
from the tool-post, or when it is very slight in body, it should 
have the top face depressed toward the cutting edge. When this 
tool is a stout one, the point may be ground more round, which 
will make it cut to finer finish. 

Boring-tool for Wrought-iron or Steel. — For turning out 
small holes, the tool here represented has no equal, providing it 




BORING-TOOL FOR WROUGHT-IRON OR STEEL. 

be made of the precise shape shown, the reasons for which are as 
follows : The cutting end must not be bent, in forginof, a^ny far- 
ther round, because, in that case, the strain placed upon the tool 
by the cut will be in a direction tending to revolve the tool in 
the tool -post, giving the tool a corresponding tendency to spring- 
away from its cut ; and further, because so stout a tool could not 
be got into the same size of hole. The degree of bend or angle 
of the centre-line of the bent end to the centre-line of the length 
of the body of the tool, causes the strain of the cut to be placed 
comparatively endwise of the tool, endeavoring to force it back 
into the tool -post, and thus places tlie strain in the direction in 
which the tool is best capable of withstanding it. The keenness 
and shape given to the top face of the tool make the cutting edge 
perform its duty on the front edge, which again tends to place 
the strain endwise on the tool, operating, by the strain on the top 
face of the tool (caused by its bending the shavinp:), to keep the 
tool to its cut by giving it an inclination to feed itself forward, 
thus relieving the feed-screw and nut of the slide-rest of a part 
of the duty of feeding. The cutting edge should not, even when 
the tool is newly forged, stand much, if any, above the horizontal 
plane of the top of the body of the tool, otherwise so stout a tool 
can not be got into a given* size of hole, a consideration which is 
of the utmost importauce ; because boring-tools, from their com- 
parative slightness, especially in long holes, are apt, under the 
most favorable of conditions, to spring away from the cut as the 
cutting proceeds toward the back end of the hole, thus making 
the latter a taper, of Avliich the back end has the smallest dianie- 
ter, necessitating several fine finishing cuts in order to make a 
parallel hole. If, however, every means is taken to use as stout 
a tool as the size of the hole will admit, the boring-tool will bore| 
a very true and smooth hole. 



MECHANICS. 



9 



In using tliese tools, it is best to employ a comparatively quick 
speed and light feed, no matter what the depth of the cut may 
be. They should be tempered to a very light straw if the tool is 
slight, and otherwise hardened right out ; and the work should 
be freely supplied with soapy water. For use on copper, the 
top face should be ground more hollow, so that the cutting edge 
will be much more keen than is here shown. Whenever there 
is sufficient room in the hole, a stout' bar of iron or steel should 
be held in the tool-post, and a short tool secured by set-screw in 
the end of the bar, thus securing greater rigidity than is pos- 
sessed by a boring-tool, and facilitating the forging and grinding 
of the cutting-tool. 

Finishing-Tool for Cast-Iron. — Cast-iron may be finished 
true and smoothly by a tool having a much broader cutting and 
scraping surface than is applicable to any other metal ; and we 
are therefore enabled to apply to it, for finishing purposes, the 




FINISHING-TOOL FOR CAST-IKON. 



tool above illustrated, setting it so that its square nose is placed 
quite parallel with the work, and feeding it with a feed almost 
as coarse as the width of the square nose, say 8 revolutions of the 
lathe per in. of tool travel on small work, and 3 revolutions per 
ditto for large work. The tool is held with the cutting edge as 
close to the tool post as can possibly be convenient, and the 
cutting speed is about 25 to 30 feet per minute on small work, 
and 18 feet on large work, the tool being hardened right out in 
all cases. 

FiNISHlNG-TOOL FOR WrOUGHT-IrON, CaST-IrON, OR StEEL.— 

This is a finishing-tool for wrought-iron which will cut smoothly, 
clean, and true, being far preferable to the square-nosed tools 
sometimes used for the purpose of finishing iron, since such tools 
do not turn wrought-iron true, but follow the texture of the 
metal, cutting deepest in the softer parts, especially when their 
edges become in the least dull from use. This tool should be 



10 



MECHANICS. 



held with the cutting edge as close in to the tool-post or clamp as 
it can conveniently be, with a quick speed and fine feed, soapy- 
water being applied to the work. It may be also used for taking 
light roughing cuts on small work, and is, for such purposes, 
an excellent tool, especially upon work so slight as to be liable 
to spring, for which purpose the cutting point should not be 
much rounded. Ground very keen, it will answer admirably for 
copper work, the cutting speed being very great ; that is to" say, 
at least fourfold that given below, which is for finishing cuts on 
wrought or cast iron. 




Size of work, 


Cutting speed, 


Qches diameter. 


feet 


per minute 


1 and less 




38 


1 to 2 




30 


2 *' 5 




25 


5 '' 12 




23 


12 ^'20 




20 


20 and over 




18 



FINISHING-TOOL FOR WROUGHT-IRON, CAST-IRON, OR STEEL. 

leed. 

30 
25 
20 
20 
16 
14 

This tool should always be liardened right out ; and if used 
upon cast-iron, it should have less keenness upon the top face 
that is to say, the plane of the top face should be ground more 
nearly to the same plane as the top face of the body of the tool. 
For use upon steel, the top face must be ground more nearly 
horizontal — a rule which, we may here observe, applies to all tools 
used upon wrought-iron. It sliould be placed in the lathe so 
that its cutting edge stands above the horizontal centre-line of the 
work. 

Front-Tool for Brass- Work. — This is a complete master- 
tool, filling every necessary qualification for all plain outside 
brass- work, and doing the duty on that metal which the front- 
tool and right and left hand side-tools do on wrought-iron. As 
shown in the engraving, it is ground to suit either roughing out 



MECHANICS. 



11 



or finisliing. For very slight work, wliicli is liable to spring, it 
may be ground a little more keen on the side faces, the top face 
Qot requiring, under any possible circumstances or conditions, to 
3e ground keener than shown above. When held far out from 
the tool-post, the top face should be ground away, sloping down 
toward the cutting edge, which is done to prevent the tool from 
jarring or chattering. It should be hardened right out, and not 




FRONT-TOOL FOR BRASS-WORK. 

lowered or tempered at all, and used for roughing out at the 
following speed and feeds : 

Size of work, Cutting speed, 

in inches. in feet. Feed. 

1 and less 350 25 

2 to 5 250 25 
5 to 12 200 25 

12 to 20 150 30 

For finishing-cuts, the cutting speed may be increased by 
about one fifth, which rule will also apply to its use upon yellow 
brass for roughing out as well as finishing purposes. 




PARTING-TOOL. 

Parting or Grooving Tool for Iron or Steel. — The part 
ing tool is applicable either to cutting grooves or for parting, or, in 
other words, cutting work apart. The cutting point, or end of the 
tool, is made thicker than the metal, both vertically and horizon- 
tally, behind it, so that the latter shall clear and not grind against 
the sides of the groove. This tool, especially if made thin to suit 
some especial purpose, is excessively liable to spring, in conse- 
quence of the pressure of the cut ; and if it commences to spring, 
it is apt to dig into the cut, and then break from the excessive 



12 



MECHANICS. 



Strain. It is to prevent tliis digging in that the top face of the 
cutting part of the tool is placed so much below the top face of 
the body of the tool, which may, however, be dispensed with when 
the cutting edge is held close in to the tool-post, and the groov- 
ing is not required to be very deep. When, however, these re- 
quirements do exist, the form illustrated is absolutely indispen- 
sable to rapid and reliable duty, whether the tool be used in a 
lathe or a planing-machine, the cutting edge of the tool bein^ 
kept at about the horizontal centre of lathe-work, by packing- 
pieces placed beneath the body of the tool. If the width of the 
tool is not less than j^g inch, and does not require to cut a groove 
deeper than f inch, it should be hardened right out ; if, however, 
these conditions are reversed, it should be tempered to a dark 
straw, and for very weak tools even to a purple color, as lower- 
ing the temper increases the strength of all tools. If the groove 
to be cut is sufficiently broad to cause the tool to spring, it is 
best to use a narrower one and cut it out in two separate cuts, 
moving the tool. 




PARTING-TOOL FOR BRASS. 



Parting-Tool for Brass. — The parting-tool for brass is gov- 
erned by the same principle as that for iron, save that its top face 
must be ground level, except in cases where the cutting edge 
stands far out from the tool-post, in which event the top face 




ROUGHING-TOOL FOR WROUGHT-IRON. 



must be ground away at an angle of which the cutting edge is 
the lowest part. It is rarely, however, necessary for brass-work 
to grind the cutting edge much below the level of the top face of 
the body of the tool, as is shown for use on wrought-iron. The 



MECHAISICS. 



13 



degree of hardness of the tool should be the same for brass as 
that given for wrought-iron. 

RouGHiNG-OUT Front Tool FOR Wrought-Iron.— The en- 
graving represents the best possible form of tool for roughing 
out wrought-iron, or for removing a large mass of that metal in 
the lathe or planing-uiachine. When used on large work, it 
should be tempered to a light straw-color, which will leave it 
strong enough to stand without breaking the heavy strain due to 
the cut. It must be held very firmly, and with the cutting edge 
as close to the tool-post as it can well be. 

The following are its rates of cutting speed and feed, the speed 
meaning the length of shaving it cuts off, and the feed implying 
the number of revolutions of the lathe necessary to feed the tool 
an inch along its cut : 



Size of work, 


Cutting speed, 


TToorl 


inches diameter. 


feet 


per minute. 


JD eec 


1 and less 




35 


25 


Ito 2 




25 


20 


2 " 5 




20 


20 


5 " 12 




18 


15 


12 " 20 




16 


12 


20 and over 




15 


12 



For work of five inches diameter, and for all sizes below that, the 
tool should be hardened right out ; that is, made as hard as fire 
and water will make it, and not tempered at all. For work of a 
larger size, it should be tempered to a light straw-color. This 
tool, with the top face ground less keen, that is, more nearly 
horizontal, is an excellent one for steel, and the harder the metal 
to be cut, the more nearly horizontal the top face must be. It 
should be placed, for lathe- work, so that the cutting edge stands 
a little above the horizontal centre-line of the work. 




SIDE-TOOL FOR BRASS. 

Side-Tool for Brass. — This tool fills the same place with re- 
ference to that metal that the side-tool and knife-tool do to iron- 
work ; and it has no superior for taking out corners, for cutting 
out holes or recesses which do not pass entirely through the 
metal. In conjunction with the front-tool for brass, already il- 
lustrated, it will perform almost any duty upon either inside or 
outside brass- work, except, of course, cutting out narrow grooves. 
Its cross-section is somewhat diamond-shaped, and it is made 
right and left by bending in opposite directions. It is a far better 
tool than those bent round at the end after the manner of a bor- 



u 



MECHANICS. 



ing-tool ; and being more rigid, it is easier to forge and grind, and 
less liable to jar or chatter. It is equally applicable as a rougliing- 
out or a finishing tool. It should be hardened right out, and 
used at the speeds and feeds given for the front-tool for brass. 




SIDE-TOOL FOR SQUARING ENDS OF WROUGHT-IRON WORK. 

Side-Tool for Squaring Ends of Wrought-Iron Work. — 
The illustration represents a side-tool for wrought-iron, to be 
employed for squaring the ends of work held between the lathe 
centres, and in other cases wherein there is not sufficient room to 
admit a stouter tool. The cutting edge is shown at A, and should 
be made more keen for wroupfht than for cast iron. In forging 
it, the hammering edgewise should be performed first, nor should 
any hammering be done to it edgewise after the steel has lost 
its redness. It should, for light duty, and for all finishing pur- 
poses, be hardened right out, and, for heavy duty, be tempered to 
a straw-color. If, however, this tool is employed, as it some- 
times is, for very heavy duty on a slotting-machine, taking a cut, 
say, 2i inches deep and -J- inch thick, it must be lowered to a 
brownish purple and used at a cutting speed of about 10 feet per 
minute, and be ground so that the cutting edge first strikes the 
cut near the body of the tool, and not at the point end. For ordi- 
nary work, it is best used with a comparatively fine feed and 
quick speed, since it is not sufficiently strong, when made very 
hard, to stand heavy duty. 




SIDE-TOOL FOR IRON. 



Side-Tool for Wrought-Iron, Cast-Iron, or Steel.— The 
engraving represents the most superior side-tool for either wrought 
or cast iron or steel, the only difference being that it requires to be 
less keen for the latter than, as here shown, for the former. It is 



MECHAKICS. 



15 



employed to cut side-faces and to take out round or square cor- 
ners. For small work, it should be made so that it will cut at 
the point, and not on both edges at one time, when used in a 
square corner. For heavy work, it may be made more round-nosed, 
and allowed to cut all round the curve ; and it will, in either 
shape, work equally well as a roughing-out or as a finishing tool, 
only requiring to be ground more keen to fit it for finishing pur- 
poses (which should be, on wrought-iron, performed with soapy 
water applied to the work), and at a faster speed and finer feed. 
For taking out a round corner or fillet in slight work, which is 
liable to spring from the pressure due to the cut, the point must 
be rounded very little, the curve being made by operating both 
the straight and cross feeds of the lathe. This tool is made right 
or left handed by simply bending it in the required direction, 
that illustrated being a left-hand tool. It should be made as 
hard as fire and water will make it, and used at the following 
speeds and feeds : 

'' '- ^—^ -" pg^^j 

30 
25 
20 
20 

When, however, it is employed for roughing-out purposes, these 
speeds may be, with advantage, slightly diminished and the feeds 
increased. 



Diameter of work, 
in inches. 


Speed, in 
feet, per minute 


1 and less 

1 to 2 

2 " 5 
5 " 12 


30 
25 

22 
20 




SPRING-TOOL. 

Spring-Tool for Use on Wrought-Iron, Cast-Iron, Steel, 
OR Brass. — The spring-tool is especially adapted to finishing 
sweeps, curves, or round or other corners, and will answer for 
any metal whatever. As illustrated, the face is given an up- 
ward incline to make it suflSiciently keen for wrought-iron or 
steel. For brass-work, this face should be made horizontally 
level, or, if the cutting stands with its cutting edge far out from 
the tool-post, it may be inclined downward to make it cut 
smoothly. The piece of wood shown driven in the bend is to 
correct any tendency of the tool to spring away from the hard 



16 



MECHANICS. 



parts of the metal, as it is apt to do. The spring-tool docs not 
turn .so true as is desirable, still the smoothness of its finish 
makes it the most desirable tool for the purposes mentioned. It 
should have its face filed up very smoothly before beino- 
hardened, and should not be ground on that face. The applica- 
tion of the oilstone greatly improves its value for finishinor. It 
should , for all purpose, be tempered to a brown color on the face, 
and left soft around the bend. 



TOOLS. 



Boring-Bar for Lathe- Work. — In boring work chucked 
and revolved in the lathe, such, for instance, as axle-boxes for lo- 
comotives, the boring-bar here shown is an excellent tool. A 
represents a ciitter-head, which slides along, at a close working 
fit, upon the bar, D D, and is provided with the cutters, B B B, 




BORING-BAR. 

which are fastened into slots provided in the head. A, by the keys 
shown. The bar, D D, has a thread cut upon part of its length, 
the remainder being plain, to fit the sliding head. One end is 
squared to receive a wrench, which, resting against the bed of the 
lathe, prevents the bar from revolving upon the lathe-centre, FF, 
by which the bar is held in the lathe. G G G are plain washers, 
provided to make up the distance between the thread and plain 
part of the bar, in cases where the sliding head, A, requires con- 
siderable lateral movement, there being more or fewer washers 
employed according to the distance along which the slidinof head 
is required to move. The edges of these washers are chamfered 
off to prevent them from burring easily. To feed the cutters, the 
nut, H, is screwed up with a wrench. 

The cutter head, A, is provided in its bore with two feathers, 
which slide in grooves provided in the bar, D D, thus prevent- 
ing the head from revolving upon the bar. It is obvious that 



MECHANICS. 



17 



tMs bar will, in consequence of its rigidity, take out a much, 
heavier cut than would be possible with, any boring-tool, and 
furthermore that, there being four cutters, they can be fed up 
four times as fast as would be possible with a single tool or cut- 
ter. 

Boring-Tools, Shapes of. — The pressure on the cutting edge 
of a tool acts in two directions, the one vertical, the other lateral. 
The downward pressure remains at all times the same ; the 
lateral pressure varies according to the direction of the plane of 
the cutting edge of the tool to tlie line or direction in which the 
tool travels : the general direction of the pressure being at a 
right angle to the general direction of the plane of the cutting 
edge. For example, the lateral pressure, and hence the spring 
of the various tools, shown in the cut, will be in each case in 
the direction denoted by the dotted lines. D is a section of a 
piece of metal requiring the three inside collars to be cut out ; 




LATERAL PRESSURE OF TOOLS. 



A, B, and C are variously shaped boring-tools, from which it will 
be seen that A would leave the cat in proportion as it suffered 
from spring, which would increase as the tool edge became dull, 
and that the cut forms a wedge, tending to force the tool toward 
the centre of the work. B would neither spring into nor away 
from the cut, but would simply require more power to feed it as 
the edge became dulled ; while C would have a tendency to run 
into the cut in proportion as it springs ; and as the tool edge be- 
came dull, it would force the tool-point deeper and deeper into 
the cut until something gave way. Now, in addition to this con- 
sideration of spring, we have the relative keenness of the tools, 
it being obvious at a glance that (independent of any top rake or 
lip) C is the keenest and A the least keen tool ; and since 
wrought-iron requires the keenest, cast-iron a medium, and -brass 
the least keen tool, it follows that we may accept, as a rule, C for 
wrought iron, B for cast-iron, and A for brass- work. In Fig. 2, B 
represents a section of the work, No. 1 represents a boring-tool 
with top-rake, for wrought-iron, and No. 2 a tool without top- 
rake, for brass- work, which may be also used for cast-iron when 
the tool stands a long way out from the tool post or clamp, under 
which circumstances it is liable to jar or chatter. A tool for use 



18 



MECHANICS. 



on wrought-iron should have the same amount of top-rake, no 
matter how far it stands out from the tool-post ; whereas one for 
use on cast-iron or brass requires to be the less keen the further 
it stands out from the tool-post. To take a very smooth cut on 
brass-work, the top face of the tool, shown at 2 in Fig. 2, must 
be ground off, as denoted by the dotted line. 

We have now to consider the most desirable shape for the 
corner of the cutting edge. A positively sharp corner, unless for 




FIG. 2. 

a special purpose, is very undesirable, because the extreme point 
soon wears away, leaving the cutting qualification of the tool 
almost destroyed, and because it leaves the work rough, and can 
only be emx)loyed with a very fine feed. It may be accepted as a 
general rule that, for roughing cuts, the corner should be suffi- 
ciently rounded to give strength to the tool-point ; while, in 
finishing cats, the point may be made as round as possible with- 
out causing the tool to jar or chatter. Now, since the tendency 



MECHANICS. 



19 



of the tool to jar or chatter depends upon four points, namely, 
the distance it stands out from the tool-post, the amount of top- 
rake, the acuteness or keenness of the general outline of the tool, 
and the shape of the cutting corner, it will be readily seen that 




VAKIOITS FORMS OF BORING-TOOLS. 



judgment is required to determine the most desirable form for any 
particular conditions, and that it is only by understanding the 
principles governing the conditions that a tool to suit them may 
be at once formed. In Fig. 3 will be found the various forms of 
boring-tools for ordinary use. No. 1 is for use when the condi- 
tions admit of a heavy cut on wrought-iron. No. 2 is for use on 
wrought-iron when the tool stands so far from the tool-post as to 
be necessarily subject to spring. No. 3 is to cut out a square 
corner at the bottom of a hole in wrought-iron. No. 4 is for 
taking out a heavy cut in cast-iron. No. 5 is for taking out a 
finishing cut in cast-iron when the tool is proportionally stout, 
and hence not liable to spring or chatter ; the point being flat, 
the cutting being performed by the front corner, and the back 
part being adjusted to merely scrape. No. 6 is for use on cast- 
iron under conditions in which the tool is liable to jar or spring. 

Chilled Cast-Iron Tools, To cast, for cutting chilled iron. — 
Make a tool of the required shape out of wrought iron, then cast 
the chilled part, using charcoal-iron No. 5. 

Chipping. — The chisel requires special notice since it is fre- 
quently made of the most ill-advised shape (for either cutting 
smoothly or standing the effects of the blow), that is, hollow, as 
in Fig. 1, in which case there are two sections of metal, repre- 
sented by the dotted lines, a a. which are very liable to break, 
from their weakness and from the strain outward placed upon 
them by the cut, which, acting as a wedge, endeavors at each 
blow to drive them outward instead of inward, as would be 



20 MECHAmCS. 

tlie case in a properly shaped chisel, as shown in Fig. 2, a being 
the cutting edge. 

When using, hold it firmly against the cut, and it will do its 
work smoother and quicker. 

The cape, or, as it is sometimes called, cross-cut chisel, is em- 
ployed to cut furrows across the work to be chipped, which fur- 
rows, being cut at a distance from each other less in width than 
the breadth of the flat chisel, relieve the flat chisel and prevent its 
corners from '' digging in" and breaking. If a large body of 
metal requires to be chipped off cast-iron or brass, the use of the 




a 



FIG. 2. 
COLD CHISELS. 

cape-chisel becomes especially advantageous, for the metal, being 
weakened by the furrows, will break away in pieces from the force 
of the blow, without requiring to be positively cut by the chisel ; 
but care must be taken to leave sufficient metal to take a clean 
finishing cut ; for when the metal is broken away, by the force of 
the blow, it is apt to break out below the level of the cut. It is 
also necessary to nick deeply with a chisel the outside edges of 
the work at the line representing the depth of the metal to be 
chipped off, so that the metal shall not break away at the edges 
deeper than the cut is intended to be. 

Chisels, Cold, To grind. — Grind a cold-chisel so that its cut- 
ting edge is rounding and not hollow, as it is often made. A 
rounded chisel is stronger and cuts smoother. A, hollow chisel 
has no useful place as a chipping-tool. 

Chisels, Cold, To harden. — Heat the chisel to a distance about 
equal to its width, immerse it about half that distance in the wa- 
ter, hold it still about four seconds, suddenly dip it a little 
deeper, and then withdraw. Brighten one flat surface with a 
piece of grindstone or an emery-block ; then brush the hand or a 
piece of waste over the brightened surface to remove tlie false 
color, and finally cool out in the water, when the clear blue color 
appears. 

Chisels, Cold, To hold. — Hold a cold-chisel firmly to its cut, 
without removing it at every blow. This will increase its effec- 
tiveness, and decrease its liability to break from a foul blow. 

Chisels, Cold, To remove burrs from the heads of. — When 
the head of a cold-chisel is burred over from use, rest the head 
upon a block of iron, and strike the burrs from the under side, 
and they will break readily and easily off. 



MECHANICS. 



21 



Chisels, Cold, Use of. — These should be kept tliin at the cut- 
ting end, which saves time and entails less labor in using. 

Cone-Plate for boring in the lathe. — For chucking shafts and 
other similar work in the lathe (to bore holes in the ends of the 
shafts, etc.), the cone-plate shown in the engraving is the best 
appliance known to machinists. A is a standard, fitting in the 
shears of the lathe, at E, and holding the circular plate, C, by 
means of the bolt, B, which should be made to just clamp the 
plate, C, tightly when the nut is screwed tight. The plate con- 
tains a series of conical holes, 1, 2, 3, etc. (shown in section at D). 
The object of coning the pin, B, where it carries the plate, C, is 
that the latter shall be made to a good working fit and have no 
play. The operation is to place the shaft in the lathe, one end 
being provided with a driver, dog, or carrier, and placed on the 
running or line centre of the lathe ; and the other end, to be 




CONE-PLATE FOR BORING -IN THE LATHE. 

Operated upon, being placed in such one of the conical holes of 
the plate, C, as is of suitable size, the distance of the standard, 
A, from the lathe-centre is to be adjusted so that the work will 
revolve in the coned hole with about as much friction as it would 
have were it placed between both the lathe-centres. Thus the 
conical hole will take the place of the dead- centre of the lathe, 
leaving the end of the shaft free to be operated on. F F are 
holes to bolt the standard, A, to the lathe shears or bed ; and Gr 
G, etc. , are taper-holes to receive the pin, G, shown in the sec- 
tional view. The object of these holes and pin is to adjust the 
conical holes so that they will stand dead true with the lathe- 
centres ; for if they stood otherwise, the holes would not be 
bored straight in the work. In the engraving, hole No. 7 is 
shown in position to operate, the pin, G, locking the plate, C, in 
that position. In setting the work, the nut on the pin, B, should 
be eased back just sufficiently to allow the plate, C, to revolve 
by hand ; the work should then be put into position, and the pin, 
G, put into place ; the standard. A, should then be adjusted to 



22 



MECHANICS. 



its distance from tlie live latlie-centre, and bolted to the lathe- 
bed ; and finally, the nut on the pin, B, should be screwed up 
tight, when the work will be held true, and the cone-plate pre- 
vented from springing. Care must be taken to supply the coni- 
cal holes, in which the work revolves, with a liberal quantity of 
oil, otherwise they will be apt to abrade. 

Cutters and Reamers, To prevent, cracking when being 
hardened. — Drill a small hole from the side to meet the large one 
at its enclosed termination. 

Cutters for Boiler-Plate and similar Work.— Cutters are 
steel bits, usually held in either a stock or bar, being fitted and 
keyed to the same ; by this means, cutters of various shapes and 
sizes may be made to fit one stock or bar, thus obviating the ne- 
cessity of having a multiplicity of these tools. Of cutter- stocks, 
which are usually employed to cut out holes of comparatively 
large diameter, as in the case of tube -plates for boilers, there are 
two kinds, the simplest and easiest to be made being that shown 
below. 




CUTTERS. 

A is the stock, through which runs a slot or keyway into vj^hich 
the cutter, B, fits, being locked by the key, C. D is a pin to 
steady the tool while it is in operation. Holes of the size of the 
pin, D, are first drilled in the work, into which the pin fits. To 
obviate the necessity of drilling these holes, some modern drill- 
stocks have, in place of the pin, D, a conical-ended pin which acts 
as a centre, and which fits into a centre-punch mark made in the 
centre of the hole to be cut in the work. Most of these devices 
are patented, and the principle upon which they act will be un- 
derstood from the second engraving, A being the stock to which 



MECHANICS. 



23 



the cutters, B B, are bolted with one or more screws. C is a spiral 
spring working in a hole in the stock to receive it. Into the out- 
er end of this hole fits, at a working fit, the centre, D, which is 
prevented from being forced out (from the pressure of the spring. 




CUTTERS. 

C) by the pin working in the recess, as shown. E is the plate to 
be cut out, from which it will be observed that the centre, D, is 
forced into the centre-punch mark in the plate by the spring, C, 
and thus serves as a guide to steady the cutters and cause them to 
revolve in a true circle, so that the necessity of first drilling a 
hole, as required in the employment of the form of stock shown 
in the first figure, is obviated. 

Cutting Square Threads, Tools for. — For cutting square 
threads, the tool here represented is used. The point at C is 



Jial4i. 




TOOL FOR CUTTING SQUAJIE THREADS. 



made thicker than the width at D, so as to give the sides clear- 
ance from the sides of the thread. At B it is made thinner, to 
give the tool clearance, and deeper to compensate in some mea- 
sure for the lack of substance in the thickness. The top face 



24 MECHANICS. 

may, for wrouglit-iron or steel, be ground hollow, C being the 
liighest point, to make it cut cleaner ; while, when held far out 
from the tool-post for use on brass-work, the face, C D, may be 
ground at an incline, of which C is the lowest point, which will 
prevent the tool from springing into the work. 

If the pitch of the screw to be cut is very coarse, a tool nearly 
one half of the width of the space between one thread and the 
next should be employed, so as to avoid the spring which a tool 
of the full width would undergo. After taking several cuts, 
the tool must be moved laterally to the amount of its width, and 
cuts taken off as before until the tool has cut somewhat deeper 
than it did before being moved, when it must be placed back 
again into its first position, and the process repeated until the re- 
quired depth of thread is attained. 



SCREW DURING CUTTING 

The above figure represents a thread or screw during the above- 
described process of cutting, a a a is the groove or space taken 
out by the cuts before the tool was moved ; B B represents the 
first cut taken after it was moved ; c is the point to which the 
cut, B, is supposed (for the purpose of this illustration) to have 
traveled. 

The tool used having been a little less than one half the proper 
width of the space of the thread, it becomes evident that the thread 
will be left with rather more than its proper thickness, which is 
done to allow finishing-cuts to be taken upon its sides, for which 
purpose the knife-tool already described is brought into requisi- 
tion, care being taken that it is placed true, so as to cut both 
sides of the thread of an equal angle to the centre-line of the 
screw. 

Adjustable dies, that is, those which take more than one cut to 
make a full thread, should never be used in cases where a solid 
die will answer the purpose, because adjustable dies take every 
cut at a different angle to the centre-line of the bolt, as explained 
by the following engravings. 

The first represents an ordinary screw. It is evident that the 
pitch from a to B is the same as from C to D, the one being the 
top, the other the bottom, of the thread. It is also evident that a 
piece of cord wound once around the top of the thread will be 
longer than one wound once around the bottom of the thread, 



MECHANICS. 



25 



and yet, in passing once around the tliread, the latter advanced 
as much forward as the former, that is, to the amount of the 
pitch of the thread. To illustrate this fact, let a h, in the follow- 
ing diagram, represent the centre-line of the bolt lengthwise, and 



jB a 




ORDINARY SCREW, 

c d Si line at right angles to it ; then let from the point e to the 
point /represent the circumference of the top of the thread, and 
from e to ^ the circumference of the bottom of the thread, the 
lines h h representing their respective pitches ; and we have the 
line k as representing the angle of the top of the thread to the 
centre-line, a h, of the bolt, and the line I as representing the 
angle of the bottom of the thread to the centre-line, a h, of the 
bolt, from which it becomes apparent that the top and the bot- 
tom of the thread are at different angles to the centre-line of the 
bolt. The tops of the teeth of adjustable dies are themselves at 
the greatest angle, while they commence to cut the thread on the 
bolt at its largest diameter, where it possesses the least angle, so 



€^ 




that the dies cut a wrong angle at first, and gradually approach 
the correct angle as they cut the depth of the thread. From what 
has been already said, it will be perceived that the angle^ of 
thread cut by the first cuts taken by adjustable dies, is neither 
that of the teeth of the dies nor that required by the bolt, so that 
the dies can not cut clean because the teeth do not fit the grooves 
they cut, and drag in consequence. 



26 MECHANICS. 

Dies for use in hand-stocks are cut from hubs of a larger dia- 
meter than the size of bolt the dies are intended to cut : this being 
done to cause the dies to cut at the cutting edges of the teeth 
which are at or near the centre of each die, so that the threads 
on each side of each die act as guides to steady the dies and pre- 
vent them from wabbling, as they otherwise would do ; the result 
of this is that the angle of the thread in the dies is not the cor- 
rect angle for the thread of the bolt, even when the dies are the 
closest together, and hence taking the finishing-cuts on the thread, 
although the dies are nearer the correct angle when in that posi- 
tion than in any other. A very little practice at cutting threads 
with stocks and dies will demonstrate that the tops of the 
threads on a bolt cut by them are larger than was the diameter 
of the bolt before the thread was commenced to be cut, which 
arises from the pressure placed on the sides of the thread of the 
bolt by the sides of the thread on the dies, in consequence of the 
difference in their angles ; which pressure compresses the sides 
of the bolt-thread (the metal being softer than that of the dies), 
and causes a corresponding increase in its diameter. It is in con- 
sequence of the variation of angle in adjustable dies that a square 
thread can not be cut by them, and that they do not cut a good 
V-thread. 

In the case of a solid die, the teeth or threads are cut by a hub 
the correct size, and they therefore stand at the proper angle ; 
furthermore, each diameter in the depth of the teeth of the die 
cuts the corresponding diameter on the bolt, so that there is no 
strain upon the sides of the thread save that due to the force ne- 
cessary to cut the metal of the bolt-thread. 

Cutting versus Scraping Tools. — A tool will either cut or 
scrape, according to the position in which it is held, as, for in- 
stance, below the line A in the illustration. Line A is in each 



CUTTING AND SCRAPING. 



case one drawn from the centre of the work to the point of con- 
tact between the tool edge and the work, C being the work, and 



MECHANICS. 



27 



B the tool. It will be observed that the angle of the top face of 
the tool varies in each case with the line A. In position 1, the 
tool is a cutting one ; in 3, it is a scraper ; in 3, it is a tool which 
is a cutter and scraper combined, since it will actually perform 
both functions at one and the same time ; and in 4, it is a good 
cutting tool, the shapes and angles of the tools being the same in 
each case. 

Dies, Fitting, to quadrants when either the dies or quadrants, 
or both, are to be hardened. — Make them a shade too small, to al- 
low for their swelling during the process of hardening. 

Dies, To ease hardened, that fit too tightly. — Supply them 
with very fine emery and oil, and work them backward and for- 
ward in their place along the travel. 

Dies, To renew worn-out. — Slightly close the holes by swaging, 
fill the clearance-holes with Babbitt-metal, and recut them with 
the hub. 




COUNTERSINK-PIN DRILLS. 

Dkills, Countersink-Pin. — Of these tools there are various 
forms. The following figure represents a taper countersink such 
as is employed for holes to receive fiush rivets or countersunk 
head-bolts, this form of tool being mainly employed for holes above 
1^6 of an inch in diameter. It should be made, tempered, and used 
as directed for pin-drills. In tempering these tools, or any others 
having a pin or projection to serve as a guide in a hole, the tool 
should be hardened right out from the end of the pin to about f of 
an inch above the cutting edges. Then lower the temper of the 
metal (most at and near the cutting-edges), leaving the pin of a 
light straw-color, which may be accomplished by pouring a little 



28 



MECHANICS. 



oil upon it during the lowering or tempering process. The object 
of this is to preserve it as much as possible from the wear due to 
its friction against tlie sides of the hole. For use on wrought-iron 
and steel, this countersink (as also the pin-drill) may have the 
front face hollowed out, after the fashion of the lip-drill, and as 
shown by the dotted line. 

Drills, Slot, for key ways. — For drilling out oblong holes, such 
as keyways, or for cutting out recesses such as are required to re- 
ceive short feathers in shafts, the drill known as a slotting-drill, 
here shown, is brought into requisition. No. 1 is the form in 



A )B 




A. A 

EDGE VIEW SIDE VIEW 

PIG. 1.— SLOT-DRILLS. 

which this tool was employed in the early days of its introduc- 
tion ; it is the stronger form of the two, and will take the heaviest 
cut. The objection to it, however, is that, in cutting out deep 
slots, it is apt to drill out of true, the hole gradually running to 
one side. The method of using these drills is to move the work 
back and forth, in a chuck provided for the purpose, the drill re- 
maining stationary. If these tools were used as common drills, 
they would cut holes of the form shown in Fig. 2. 

Files, The use of. — In draw-filing, take short, quick strokes, 
which will prevent the file from pinning and scratching. Long 



MECHANICS. 



29 



strokes, no matter liow long the work may be, are useless save to 
make scratches. Remember that it is less the number of strokes 
you give the file than the weight you place upon it that is effec- 
tive ; therefore, when using a rough file, stand sufficiently away 
from the vise to bring the weight of the body upon the forward 
stroke. New files should be used at first upon broad surfaces, since 
narrow edges are apt to break the teeth if they have the fibrous 
edges unworn. For brass-work, use the file on a broad surface 




PIG. 2.— SLOT-DRILLS. 

until ts teeth are dulled, then make two or three strokes of the 
file under a heavy pressure upon the edge of a piece of sheet-iron, 
which will break off the dulled edges of the teeth, and leave a 
new fibrous edge for the brass-work. Use bastard-cut files to 
take off a quantity of metal of ordinary hardness ; second-cut, in 
fitting, and also to file unusually hard metal ; smoothing, to fin- 
ish in final adjustment or preparatory to applying emery-cloth ; 
dead smooth, to finish very fine work ; float-file on lathe- work. 

Files, To prevent scratching by. — To prevent files from pin- 
ning, and hence from scratching, properly clean them, and then 
chalk them well. 

Files, To resharpen. — (1) Carefully clean them with hot water 
and soda, then place them in connection with the positive pole of 
a battery in a bath composed of 4 parts of sulphuric acid and 100 
parts water. The negative pole is to be formed of a copper spi- 
ral, surrounding the files but not touching them ; the coil termi- 
nates in a wire reaching above the surface. Leave the files in 
the bath ten minutes, then carefully wash them off, dry, and oil. 
(2) Carefully clean the files in hot water and soda, and dip for 40 
minutes in nitric acid of 41° B. 

Files, To select. — To choose a flat file, turn it edge upward, 
and look along it, selecting those that have an even sweep Irom 
end to end, and having no flat places or hollows.^ To choose a 
half-round file, turn the edge upward, look along it, and select 
that which has an even sweep, and no flat or hollow places on the 
half-round side, even though it be hollow in the length of the 
flat side. 

Gravers, Grinding. — Gravers should be ground on the end 
only, and not on the sides of the square, except when applied to 
brass- work. 

Half-Rotjnd Bits. — For drilling or boring holes very true and 
parallel in the lathe, the half-round bit shown in the engraving 



30 



MECHANICS. 



is-unsurpassed. The cutting edge, A, is made by backing off the 
end, as denoted by the space between the lower end of the tool 
and the dotted line, B, and performing its duty along the radius, 
as denoted by the dotted line in the end and top views. It is only 
necessary to start the half-round bit true, to insure its boring a 
hole of any depth true, parallel, and very smooth. To start it, 
the face of the work should, if circumstances permit, be made 
true ; this is not, however, positively necessary. A recess, true 
and of the same diameter as the bit, should be turned in the 
work, the bit then being placed in position, and the dead-centre 
employed to feed it to its duty, which (if the end of the bit is 
square, if a flat place be filed upon it, or any other method of 
holding it sufficiently tight be employed) may be made as heavy 
as the belt will drive. So simple, positive, and effective is the 
operation of this bit that (beyond starting it true and using it at 
a moderate cutting speed, with oil for wrought-iron and steel) no 
further instructions need be given for its use. 




SIDE mw 




FIG. 1.— HALF-ROUND BITS. 

In Fig. 2 is shown A, a boring-bar ; B B is the sliding head ; 
C C is the bore of the cylinder, and 1, 2, and 8 are tools in the 
positions shown. D D D are projections in the bore of the cylin- 
der, causing an excessive amount of duty to be placed upon the 
cutters, as sometimes occurs when a cut of medium depth has 
been started. Such a cut increases on one side of the bore of the 
work until, becoming excessive, it causes the bar to tremble and 



MECHANICS. 



31 



the cutters to chatter. In such a case, tool and position No. 1 
would not be relieved of any duty, though it spring to a consider- 
able degree ; because the bar would spring in the direction de- 
noted by the dotted line and arrow E, while the spring of the 
tool itself would be in the direction of the arrow, F. The ten- 
dency of the spring of the bar is to force the tool deeper into 
the cut instead of relieving it ; while the tendency of the spring 
of the tool will scarcely affect the depth of the cut. Tool and 
position No. 2 would cause the bar to spring in the direction of 
the dotted line and arrow G, and the tool itself to spring in the 
direction of H, the spring of the bar being in a direction to in- 
crease, and that of the tool to diminish, the cut. Tool and posi- 
tion No. 3 would, however, place the spring of the bar in a direc- 




FIG. 2.— HALF-ROUND BITS. 

tion which would scarcely affect the depth of the cut, while the 
spring of the tool itself would be in a direction to give decided 
relief by springing away from its excessive duty. It must be 
borne in mind that even a stout bar of medium length will spring 
considerably from an ordinary roughing-out cut, though the lat- 
ter be of an equal depth all round the bore, and from end to end 
of the work. Position No. 3, in Fig. 2, then, is decidedly prefer- 
able for the roughing-out cuts. In the finishing cuts, which 
should be very light ones, neither the bar nor the tool is so 
much affected by springing ; but even here position No. 3 main- 
tains its superiority, because, the tool being pulled, it operates 
somewhat as a scraper (though it may be as keen in shape as the 
other tools), and hence it cuts more smoothly. It possesses, it is 
true, the defect that the distance from the cutting point stands 
further out from the holding-clamp, and the tool is hence more 
apt to sprinir ; and in cases where the diameter of the sliding 
head is muchless than that of the hole to be bored, this defect 
may possess importance, and then position No. 2 may be prefer- 



32 MECHANICS. 



able ; but it is an error to employ a bar of small diameter com- 
pared to that of the work. 

To obtain the very best and most rapid result, there should be 
but little space between the sliding head and the bore of the 
work ; the bar itself should be as stout as is practicable, leaving 
the sliding head of sufficient strength ; and if the bar revolves in 
journals, these should be of large diameter and with ample facili- 
ties for taking up both the diametrical and end play of the boxes, 
since the one steadies the bar while it is performing boring duty, 
and the other while it is facing off end faces, as for cylinder-cover 
joints. 

Hammers, Chipping. — These should weigh about If lbs., and 
have handles 15 inches long. 

Metal having a tery hard Skin, Tools used for. — When 
the skin of the metal to be cut is unusually hard, as frequently oc- 
curs in cast-iron, the shape of the cutting part of the boring-tool 
must be such that its point will enter the cut first, so that it cuts 
the inside and softer metal. The hard outside metal will then 
break off with the shaving without requirincr to be cut by the tool 
edge, while the ancrle of the cut will keep the tool point into its 
cut from the pressure required to break the shaving. A tool of 






FIG. 1.— TOOL FOR HARD METAL. 

this description is represented in the engraving, Fig. 1. a is the 
point of the tool, and from a to B is the cutting edge ; the dotted 
lines, c and D, represent the depth of the cut, c being the inside 
skin of the metal, supposed to be hard. The angle at which the 
cutting edge stands to the cut causes the pressure, due to the 
bending and fracturing of the shaving, to be in the direction of e, 
which keeps the tool point into its cut ; while the resistance of 
the tool point to this force, reacting upon the cut, from a to B, 
causes the hard skin to break away. For use on wrought-iron, 
however, the tool presented below will work to better advantage, 
it being a side-tool. In the event of a side face being very hard, 
it possesses the advantage that the point of the tool may be made 
to enter the cut first, and, cutting beneath the hard skin, fracture 
it off without cutting it, the pressure of the shaving on the tool 
keeping the latter to its cut, as shown in Fig. 2. 

a is the cuttinor part of the tool ; B is a shaft with a collar on 
it ; CIS the side cut beincr taken off the collar, and D is the face, 
supposed to be hard. The cut is here shown as being commenc- 
ed from the largest diameter of the collar, and beinff fed inward 
so that the point of the tool may cut well beneath the hard face, 
D^ and so that the pressure of the cut on the tool may keep it to 



MECHANICS. 



33 



its cut, as already explained ; but the tool will cut equally as ad- 
vantageously if the cut is commenced at the smallest diameter of 
the collar and fed outward, if the skin, D, is not unusually hard. 




TOP VIEW 



FIG. 2. — TOOL FOR HAKD METAL. 

Plane-Irons, Carpenters', To grind. — The angle of a plane- 
iron should be about 25°. 

Plane-Irons, Angle of, to face of planes. — For soft wood, 50° ; 
for mahogany, 50° ; for soft wood for mouldings, 55° ; for hard 




DEVICE FOR GRINDING PLANE-IRONS. 

wood for mouldings, 60°. With this device, one man can both 
turn the stone and grind the tool much more accurately than 
by holding it in his hand. 



34 MECHANICS. 

A is a piece of spring-steel, 8 inclies long, bent at each end, 
with thumbscrew. You grasp the holder with the left hand at 
B, sticking the point, C, into a board or the wall, at such a dis- 
tance from the stone as to bring the iron, D, in the right position 
on the stone. By raising or lowering C, the bevel is regulated. 

Saws and Springs, Hardening. — The usual way of proceed- 
ing is to heat the saws in long furnaces, and then to immerse 
them horizontally and edgewise in a long trough containing the 
composition ; two troughs are commonly used alternately. Part 
of the composition is wiped off with a piece of leather, when the 
articles are removed from the trough ; they are then heated one 
by one over a clear coke fire until the grease inflames ; this is 
called '^ blazing off.'' A greatly recommended composition 
consists of 2 lbs. of suet and J lb. of beeswax to every 
gallon of whale oil ; these are boiled together, and will 
serve for thin articles and most kinds of steel. The addi- 
tion of black resin, to the extent of about 1 lb. to the 
gallon, makes it serve for thicker pieces, and for those it 
refused to harden before ; but the resin should be added with 
judgment, or the articles will become too hard and brittle. The 
composition is useless when it has been constantly employed for 
about a month ; the period depends, however, on the extent to 
which it is used, and the trough should be thoroughly cleaned 
out before the new mixture is placed in it. The following 
recipe is commended : 20 galls, spermaceti-oil, 20 lbs. 
melted and strained beef suet, 1 gall, neats'-foot oil, 1 lb. 
pitch, 3 lbs. black resin. These last two articles must be 
previously melted together, and then added to the other in- 
gredients ; the whole must then be heated in a proper iron 
vessel, with a close cover fitted to it, until the moisture is 
entirely evaporated, and the composition will take fire on a flam- 
ing body being presented to its surface ; the flame must be in- 
stantly extinguished again by putting on the cover of the vessel. 
When the saws are wanted to be rather hard, but little of the 
grease is burned off ; when milder, a large portion ; and for a 
spring temper, the whole is allowed to burn away. When the 
work is thick, or irregularly thick and thin, as in some springs, 
a second and third dose is burned off*, to insure equality of 
temper at all points alike. Gun-lock springs are sometimes lite- 
rally fried in oil for a considerable time over a fire in an iron tray. 
The thick parts are then sure to be sufficiently reduced, and the 
thin parts do not become the more softened from the continuance 
of the blazing heat. Springs and saws appear to lose their 
elasticity after hardening and tempering, from the reduction and 
friction they undergo in grinding and polishing. Toward the 
conclusion of the manufacture, the elasticity of the saw is re- 
stored principally by hammering, and partly by heating over a 
clear coke fire, to a straw-color ; the tint is removed by very 
diluted muriatic acid ; after which the saws are well washed in 
plain water and dried. 

Saws, Band, To solder.— Scarf the end of the saw to a taper for 
a distance of two fine or one coarse tooth, fitting the edges of the 
scarf very true and level. Clean the joint with acid, and clamp the 



saw, 


Revolutions per minute for 


inches. 


English or thin saws. 


36 


1000 


30 


1200 


25 


1400 


20 


1500 


15 


1800 


10 


2900 



mecha:n^ics. 35 

saw ends together with a suitable frame or clamp. Heat the 
joint with a pair of red-hot tongs, and place a small strip of 
jeweler's silver solder upon the joint ; press it upon the same 
with the red-hot tongs. As soon as the solder has properly run 
or flowed, remove the tongs and cool the joint with water, to re- 
store as far as possible the temper of the saw. Then file the 
joint to an even thickness and level with the rest of the saw, 
using a wire gauge as a template. 
Saws, Circular, Speeds for : 

Diameter of 

Revolutions per minute for 
American or thick saws. 

1500 
1800 
2100 
2400 
2700 
3000 

Circular saws of over 40 or 50 inches in diameter are, or should 
be, hammered to run at a certain speed. This is more important 
when the speed is as high as from 700 or 900 revolutions per 
minute. If a saw is so hammered as to do good work at 300 or 
400 revolutions per minute, it will not do as good work at 900, for 
the reason that the high speed expands the outside or rim, causing 
it to dish, or "flop around," as sawyers sometimes express it. In 
such cases, and when it is inconvenient to reduce the speed, it 
will be necessary to guide the saw out of the log so as to cause 
the central part to rub against the log enough to heat it slightly, 
thus expanding the portion that needs hammering. An expert 
sawyer can in this way manage indifierently well, though at an 
expense of considerably more power. A large saw, to run well 
at high speed, should be hammered in the centre part until it is 
slightly dishing, or, as it is variously expressed, ''loose at the 
eye,'' or *' rim-bound.'' It may be loose at the eye when it is the 
reverse of rim-bound, namely, too open at the rim, which is the 
most frequent trouble with such saws. They all become so 
eventually from use, and should then be rehammered. 

Saws, Hints concerning. — A saw just large enough to cut 
through a board will require less power than a saw larger, the 
number of teeth, speed, and thickness being equal in each. The 
more teeth, the more power, provided the thickness, speed, and 
feed are equal. There is, however, a limit, or a point where a 
few teeth will not answer the place of a larger number. The 
thinner the saw, the more teeth will be required to carry an equal 
amount of feed to each revolution of the saw, but always at the 
expense of power. When bench-saws are used, and the sawing 
is done by a gauge, the lumber is often inclined to clatter and to 
raise up the back of the saw, when pushed hard. The reasoTi is 
that the back half of the saw, having an upward motion, has a 
tendency to lift and raise the piece being sawn, especially when 
it springs and pinches on the saw, or crowds between the saw and 
the gauge ; while the cut at the front of the saw has the opposite 
tendency of holding that part of the piece down. The hook or 



36 MECHANICS. 



pitch of a saw-tooth should be on a line from J to ;^ the diame- 
ter of the saw : a ^ pitch is mostly used for hard, and a J- for 
softer timber. For very fine-toothed saws designed for heavy 
work, such as sawing shingles, etc., even from soft wood, J pitch 
is best. 




SAW-TEETH. 



Saw-Teeth, Shapes of. — No. 1 is a good-shaped tooth for very 
soft wood, the wide bevel being the front of the tooth. The 
point would be liable to break or bend in very hard wood or in 
knots. No. 2 will stand to saw the hardest timber or knots, but 
will not cut as easily as No. 1. No. 3 is a form of point general- 
ly used for promiscuous sawing of both hard and soft wood. The 
set must be wide enough to clear the plate. After filing your 
saw, place it on a level board and pass a whetstone over the side 
of the teeth until all the wire-edge is off them. This will make 
the saw cut true and smooth, and it will remain sharp longer. 
The saw must be set true with a saw-set. 

Scrapers, To make. — Old files which have never been recut 
make excellent scrapers. 

Scrapers, Use of. — All work should be fitted as nearly true as 
possible before being scraped with the flat scraper, which is in- 
tended for flat surfaces only. For hollow work, curves, etc., the 
half-round scraper is the best, the three-cornered being the least 
efficient of all scrapers. 

Taps and Reamers, Finishing. — The forgings are got out in 
the usual way, left to anneal, centred, and turned just sufficient to 
remove the scale. Then anneal again, and turn down to within 
-Jy inch, or less, of finishing size. Anneal once more, and finish 
in the lathe. If not sprung in turning, the tap or reamer will 
come out all right when hardened. This has been tested success- 
fully with taps from | inch in diameter and 3 inches long up to 
those of 1 inch in diameter and 2 feet long. 

Taps, Tempering and hardening. — To harden a tap, heat to a 
cherry-red, in a clear and not a blazing fire, or, what is better, 
heat in charcoal, holding the tap by the square end ; dip it 
endwise in the water, immersing the whole of the threaded part 
first, and holding it still until the plain part is of a very low red ; 
slowly immerse the remainder, holding it still, when fully im- 
mersed, until it is quite cold. Then brighten the flutes, and tem- 
per as follows : Heat a piece of tube (with a bore about twice the 
diameter and a length one half that of the tap) to a bright red 
heat, take it from the fire, set it up vertically, and hold the tap in 
the centre of the tube, with the plain part of the tap in the tube 



MECHANICS. 



37 



and the thread part projecting. Revolve it in this position suffi- 
cient time to heat the plain end about as warm as the hand can 
bear it ; then keep revolving the tap and moving it endwise back 
and forth through the tube until the thread will color to a deep 
brown and the shank to a brown purple. If any unevenness ap- 
pears in the color, hold the parts having the lighter color a little 
longer in the tube, or cool the part coloring too deeply by apply- 
ing a little oil to it. Perform the whole process slowly, taking 
the tap from the tube to retard it, if necessary. 

Taps, Tempering. — The squares of taps should be tempered to 
a blue. 

Taps, To temper, without springing.-— Forge the tap with a 
little more than the usual allowance, being careful not to heat 
too hot, nor to hammer too cold. After the tap is forged, heat it 
and hold it on one end upon the anvil. If a large one, hit it with 
the sledge ; if a small one, the hammer will do. During this ope- 
ration, the tap will give way on its weakest side and become bent. 
Do not attempt to straighten it. On finishing and hardening the 
tap, it will become perfectly straight. 

Tools, Spring of. — To obviate the spring of tools which must, 
of necessity, be held out a long way from the tool-post, the ful- 
crum off which the tool springs must be adjusted so as not to stand 
in advance of the cutting edge of the tool. In the engraving, a 
represents the fulcrum off which the tool takes its spriug ; B is 
the work to be cut ; and the dotted line, C, is the line in which 




SPRING-TOOL. 



the point of the tool would spring: (being in the direction denoted 
by the arrow), which is not in this case into the cut, but rather 



38 MECHANICS. 



away from it, in consequence of the point of the tool standing 
back from a line perpendicular to the line of the back part of the 
tool, as shown by the dotted line, D. 



MECHANICAL SHOP-WRINKLES AND 
DIRECTIONS. 

Annealing Iron and Steel. — Save the scales from the forge 
(oxide of iron) for this purpose. 

Anvils, Tempering. — This can be done by simply heating the 
anvil and immersing it in a tank of cold water to a depth of two 
or three inches. Play a stream of water from a hose on the face. 

Axles, Value of hollow. — An old apprentice of Sir William 
Fairbairn writes : " For several years it has cost me five dollars 
a week to keep the bolts on my trip or cushioned hammer-heads 
in repair, and, finding it to wear on my patience, I tried all kinds 
of iron, but to no use ; break they would. I finally bored a hole, 
one third the diameter of the bolts (1^ in.), and put a f in. 
hole down, some way below the thread, which formed a tube. I 
have now run them for three months, and they show no signs of 
giving out. The wrench used would break the other bolts easily ; 
but it can not do so with these. My work on spindles requires 
the dies to snap together about nine times in ten, which tells very 
severely on the bolts." 

Bending Copper Pipes. — Fill them with resin or lead, which 
will prevent them from buckling in the bends. 

Bolts and Studs, Standing. — When these are placed in posi- 
tions liable to corrode them, they should have the standing ends 
^ in. larger than the end receiving the nut, and the plain part 
should be square. By this means a wrench may be applied to 
extract them when necessary. The stud, also, is not so likely to 
break oflPin consequence of weakness at the junction of the thread 
and the plain part, where the groove to relieve the termination of 
the thread is cut. 

Bolts or Studs, Standing, To unscrew. — Studs that have be- 
come so corroded in their holes that they are liable to break off, 
should be well warmed by a red-hot washer ; because the strength 
of the stud increases by beinor heated up to about 400° Fahr., and 
therefore studs which readily twist off when cold will unscrew 
when heated to about that temperature. Nuts upon standing 
bolts of studs, in the smoke-boxes of locomotives, or in similar 
positions, which have become so corroded as to endanger twisting 
off, should be cut throuofh on one side with a cape or cross-cut 
chisel, thus saving the stud at the expense of the nut. The split 
must be cut from the end face of the nut to the bedding face. 

Brasses, Bedding down. — In bedding down brasses or journal- 
boxes of any description, the followin<if plan should bo employed 
to gauge how much requires to be chipped or filed away from any 



MECHANICS. 39 

part or parts of the bed of the brass to enable it to bed to its seat 
all over : Take ordinary red marking (which should be composed 
of Venetian-red and common oil, mixed to the consistence of a 
thick paint), and paint over the whole bed into which brass is to 
he fitted. Then take some putty (mixed stiffly), and rolling it 
into pellets about the size of a large pea, place them here and 
there upon the painted surface. Then drive the brass home, and 
drive it out again, when it will be found that the thickness to 
which the pellets have been smashed by the bottom of the brass 
registers to the greatest possible exactitude how near the bottom, 
of the brass comes to the bed of the bottom of the bearing, indi- 
cating precisely the amount to be chipped and filed ofE the bottom 
of the brass to bed it. It is better, however, to be careful not to 
take too much off at first, and to repeat the process with the pel- 
lets. It must be borne in mind carefully to replace the old pel- 
lets with new ones at each trial, otherwise you will be misled. 
The object of painting the bottom of the box with red marking, 
before placing the pellets, is to cause the latter to stick to the 
box and not to the brass, and to prevent them from falling out 
when the box is turned upside down to drive the brass out. This 
is the only practical method of ascertaining how much to take off 
a brass to bed it, and will be found an easily applied and almost 
invaluable assistance. 

Brasses, Fitting. — In doing this, a piece of wood must be 
used to hammer on in driving them in and out, since driving 
them with the bare hammer, a piece of metal, or a mandril, 
stretches the skin and enlart^es the diameter across the bore ; 
then when the brasses are bored and the stretched skin is con- 
sequently removed, the brass resumes its original shape, and 
hence becomes loose in the strap or box. In fitting brasses to 
their places, leave them a little too tight, since all brasses con- 
tract a little across the bore in consequence of the process of 
boring. This rule applies also to journal-boxes of cast-iron or 
any other metal. 

Brasses, Setting. — In setting brasses or any other journal- 
boxes to be bored, place a piece of sheet-tin between the joint of 
the brasses, and bore the brasses or boxes the thickness of the 
tin too large, which thickness may be gauged by placing a small 
piece of the same tin under the leg of the inside calipers when 
trying the bore. The reason for this is that practice demon- 
strates it to be an invariable rule that a half-circle or half -hole, 
whether in a movable brass or in a solid box, will never fit 
down upon its journal, but will bind upon the edges across the 
diameter, and must therefore be scraped or filed on the sides to 
let the crown down. This defect is obviated by the employment 
of the sheet-tin as described, which will save three fourths of 
the time usually required to fit such work to a good bearing. 
This plan is highly advantageous in boring eccentric straps and 
large brasses ; and the larger the size, the thicker the tin may be. 

Brass Turnings and Filings, To melt, with little waste. — 
Compress in a crucible until it is full^ then cover, and lute the 
top with pipe or fire-clay. 



40 MECHANICS. 

Burr Stones, Filling holes in.— Use melted alum mixed with 
burr-stone pulverized to the size of grains of sand. 

Burrs, To prevent heating,— Dress from centre to circum- 
ference, leaving no bosom. Draw a line across the centre, each 
way, dividing a four-foot burr into 16 squares or divisions, and 
other sizes, more or less, in the same proportion, with all straight 
furrows. Let the draft be i the diameter of the rock. Lay off 
the lands and furrows i inch each, observing to dress smooth. 
Sink the furrow at the eye i inch deep for corn, and run out to 
tV at the periphery ; for wheat, 1% at the eye, and i at the peri- 
phery. When thus finished, crack the lands in straight lines, 
square with the draft of cross-lines, so as to make the lands face 
in the runner and bed direct. This will never heat. 

Carpenter's Bench, To make a. — Take three pieces of 2 x 5 
in. stuff, 3 feet long, for supports for top. Take two 12 in. 
boards, 12 feet long and 1 in. thick, for sides ; nail the side- 
boards firmly on to the ends of the 2 x 5 cross-pieces, and put on 
a top of suitable material, and you have a bench without legs. 
Then take four pieces of 2 x 5 in. stuff" of the desired height for 
the legs, and frame a piece 1x3 inches across each pair of legs, 
6 inches from the bottom of the leg, putting the legs at the pro- 
per distance apart for width of bench. Cut a fork or slit in the 
top end of each leg, so as to straddle the cross-piece at the ends ; 
put a 3i X I in. bolt through each leg and the side-board, and 
you have a good solid bench, that can be taken down in five 
minutes by simply removing the four bolts. It can also be taken 
through any door or window, or down or up stairs, or to any 
place required. 

Castings, Brass.— These shrink i inch to the foot in cooling. 

Castings, Copper, To prevent air-holes in.— Cast in green sand, 
and not in dried moulds, using li lbs. zinc as a flue, as pure 
copper will not run sufficiently freely to prevent honeycombing. 

Castings, Copper.— These shrink J inch to the foot in cooling 
in the moulds, and also shrink (as do all other castings) most 
where there is the greatest substance of metal. 

Castings, Holes in, To prevent.— In casting iron on iron or 
steel spindles, the moulds are cast endwise, letting the cast 
metal covering the spindle be an inch longer on the uppermost 
side than is necessary when the job is finished ; thus the air- 
holes, if any, will form in the extra inch of length, and may be 
cut off in the lathe. 

Castings, Iron. — These shrink fo inch to the foot in cooling in 
the moulds. 

Castings, Shrinkage of. — Shrinkage sideways and endwise, on 
castings of 3 inches and less size, is compensated for by the 
shake in the sand given by the moulder to the pattern in order 
to extract it from the mould. 

Castings, Small. — In very small castings requiring to be of 
correct size, allowance should be made in the pattern for the 
shake of the pattern in the sand, thus : A pattern of an inch cube 
will require to be made -^ inch less endwise and sideways, and 



MECHANICS. 



41 



tlie usual allowance above an inch must be made on tlie top face 
of the pattern, which should have ' ' top" marked on it ; thus the 
shake endwise and sideway s given to the pattern, in order to ex- 
tract it without lifting the sand, will be allowed for in the size 
of the pattern. The effect of this shake in the sand is appreci- 
able in patterns up to about four inches diameter. It is a com- 
mon practice to cool brass castings in order to loosen or remove 
the sand from the surfaces. The effect is to place conflicting 
strains and tensions upon tlie whole skin of the metal, which will 
alter its shape when the outer skin of such faces is removed ; so 
that, supposing the casting to be a cube, no one face will be 
either true of itself or with the others when it has been planed, 
no matter how true the surfacing may have been performed. 

Castings, Smooth. — A means highly recommended for obtain- 
ing very smooth castings, is mixing with the green foundry sand 
forming the mould about ^S part of tar, a mixture which is em- 
ployed without the addition of any other substance. 

Castings, To estimate the weight of. — 



A pattern weighing 1 lb., and made 
of 



Mahogany 

** (St. Domingo), 

Maple 

Beech 

Cedar 

Yellow Pine 

White Pine. 



Will weigh when cast in 



Cast 
Iron. 



8 
10 
10 
11 
11.5 
13 
14 



Zinc. 


Copper. 


YeUow 
Brass. 


8 


10 


9.8 


9.5 


12 


11.5 


9.8 


12.5 


12 


11 


14 


1&.4 


11.4 


14.5 


14 


12.6 


16 


15.5 


14.5 


18 


17.5 



Gun 
Metal. 



10 
12 

13.8 
14.5 
16 
17.8 



Example : The pattern of a wheel made of cedar weighs 8 lbs, 
how much will a casting of iron weigh ? 8 lbs. weight of pat- 
tern multiplied by 11.5, which is the multiplier for iron set oppo- 
site cedar, equals 92.0 weight of casting. 

Chuck-Cement, Removing, from lathe-work. — Warm the ob- 
ject over a spirit-lamp, and tap lightly with a stiff brush ; the 
wax will adhere to the latter. If in a hurry, a few seconds' boil- 
ing in alcoliol will remove the remainder of the wax. 

Chuck-Lathe, An electric. — In order to obviate the inconve- 
nience and loss of time involved in the ordinary mode of fixing 
upon a lathe- chuck certain special kinds of work, such as thin 
steel disks or small circular-saws, the chuck may be converted 
into a temporary magnet, so that the articles, when simply placed 
on the face of the chuck, are held there by t'-ie attraction of the 
magnet ; and, when finished, can be readily detached by merely 
breaking the electric current and demao-netizing the chuck. The 
face-plate of the magnetic chuck is composed of a central core of 
soft iron, surrounded by an iron tube, the two being kept apart 
by an intermediate brass ring ; and the tube and core are each 



42 MECHANICS. 



surrounded by a coil of insulated copper wire, tlie ends of which 
are connected by two brass contact-rings that encircle the case 
containing the entire electro-magnet thus formed. These rings 
are grooved, and receive the ends of a pair of metal springs con- 
nected with the terminal wires of a battery, whereby the chuck is 
converted into an electro-magnet capable of holding firmly on its 
lace the article to be turned or ground. For holding articles of 
larger diameter, it is found more convenient to use an ordinary 
face-plate, simply divided into halves by a thin brass strip across 
the centre ; a horseshoe-magnet, consisting of a bent bar of soft 
iron, with a coil of copper wire around each leg, is fixed behind 
the face-plate, each half of which is thus converted into one of 
the poles of the magnet. The whole is inclosed in a cylindrical 
brass casing, and two brass contact-rings, fixed around this casing, 
are insulated by a ring of ebonite, and are connected with the two 
terminal wires of the magnet-coils. A similar arrangement is 
also adapted for holding work upon the bed of a planing or drill- 
ing machine, in which case the brass contact-rings may be dis- 
pensed with, and any desired number of pairs of the electro-mag- 
netic face-plates are combined so as to form an extended surface 
large enough to carry large pieces of work. For exciting the 
electro-magnet, any ordinary battery that will produce a continu- 
ous current of electricity can be used. 

Cocks, To grind plugs in. — The best material for this purpose 
is the red, well -burnt sand from the core of a brass casting, the 
sand being sifted, before using, through fine wire gauze. It will 
cu^^-n^^ TO truly and smoothly than any other material, and should 
be Ud_ / wv^ji water, and not oil. After the cock is sufficiently 
ground, wash it and the barrel with clean water ; and after wip- 
ing them comparatively but not quite dry, revolve the plug 
backward and forward in its place under a slight pressure, and 
the surface will assume a rich brown color, showing very dis- 
tinctly the precise nature of the fit, and leaving a smooth sur- 
face, free from grit and not liable to either jam or abrade. 
Valves may be ground to their seats in a similar manner. 

Cones in Holes, Fitting. — Rub the cone with either red mark- 
ing or else chalk, giving it in either case a very thin coat. A 
narrow strip of marking, running from end of the cone, will do. 
Put the cone into its place, press it forward and revolve it back 
and forth, and the marks will show where it binds. 

Connecting-rods, Fitting. — When the cross-head and crank- 
pin are in their places upon the engine, fitting may be done 
as follows : Connect the cross-head end of the rod in its place 
upon the cross-head journal, keeping the other end clear of the 
crank-pin; put the brasses and keys in their places in the rod 
end, then lower the crank-pin end upon the crank-pin journal, 
which will show whether the cross-head journal leads true ; if 
it does not, move the crank-pin end of the rod back and forth, 
exerting a side pressure on it in the direction in which it wants 
to go, so as to plainly mark where the connecting-rod brasses of 
the cross-head end require easing; and after the cross-head end 
is adjusted, put the crank-pin of the rod upon its place upon the 



MECHANICS. 43 

crank-pin, keeping the cross-head end clear of the cross-head ; 
put the brasses, keys, etc., in their places, and proceed as before. 
Red marking should be rubbed on both the crank-pin and cross- 
head journals, so as to mark the brasses plainly. A half-round 
file and half-round scraper should be used to adjust and ease 
the brasses. 

Connecting-rod Straps, To close the jaws of.— If the jaws 
are too wide at the points, rest the strap upon the two ends, and 
(with a round pene-hammer) lightly hammer the outside of the 
crown of the strap all over, taking care to hammer it evenly, so 
as not to leave any deep hammer-marks. 

Connecting-rod Straps. — To open the jaws of a connecting- 
rod strap, hammer the inside face of the crown of the strap lightly 
and evenly all over with a round pene-hammer. To bring back to 
its original shape a strap that has been opened or closed in its 
width between the jaws, by being pened with a hammer, remove 
by filing -}^ inch in depth of the surface that has been hammered, 
or heat the part hammered to a low red heat. 

Connecting-rod Straps, Refitting, to rods.— Place the gib and 
key in the strap to prevent it from warping, and heat the crown end 
of the strap to a bright red ; on taking it from the fire, remove 
the scale by lightly filing with a coarse file ; then plunge the 
strap to nearly half the thickness of the crown in water, and 
after holding it there for about ten seconds, slowly immerse the 
remainder of the strap in the water, and withdraw when quite 
cold. It will be found to have closed along its whole length, al- 
though mostly at the points. 

Copper or Brass, To soften. — Heat to a low red heat, and 
plunge in salt water. 

Copper, To harden. — Copper may be slightly hardened by 
closing the grain. This can be done by lightly hammering its 
surface with a round pene-hammer. 

Corundum- Wheels, To true. — The wheel being adjusted in 
the lathe, revolve it very fast, holding a piece of corundum-stone 
against the uneven or wabbling surface. In a short time, the 
piece will melt and unite itself to the wheel, so as to make the 
latter perfectly true. 

Cotton- Waste, To clean greasy. — Boil it in a strong solution 
of common soda in water, and save the resultant soapy liquid to 
keep your drills and reamers wet when boring iron. 

Crank-pins, Riveting. — In riveting over the end of a crank- 
pin, apply the hammer most around the outer circumference and 
least toward the centre ; this will prevent the riveted end from 
splitting. 

Emery, for grinding purposes. To prepare fine. — When no 
fine emery is at hand, place coarse emery upon an iron block or 
plate, and hammer it well with the face end of the hammer ; after 
which, grind it by abrasion with the hammer face. 

Emery- Wheels, Speed of. — A 6-inch emery-wheel should 



44 MECHANICS. 



make about 2400 revolutions per minute ; an 8-incli, 1800 ; a 12- 
incb, 1200. 

Engine-room Chairs. — Good cliairs for engine-room or factory 
use are easily made of light gas-pipe. 

Grease, To clean, from bolts. — Moisten in benzine, roll in saw- 
dust, and brush afterward. 

Grindstones, Care of. — These should never be left in the sun- 
liofht, or with one side standing in water, since heat evaporates the 
water in the stone, leaving it harsh and hard, wliile saturation 
softens it. The grindstone is a self-sharpening tool ; and after 
being turned in one direction for some time (if a hard stone), 
the motion should be reversed. Sand of the right grit applied 
occasionally to a hard stone will improve it. 

Grindstones, Selecting. — When you get a stone that suits 
your purpose, send a sample to the dealer to select by; a half- 
ounce sample is enough, and can be sent by mail. 

Grindstone-Spindles. — Common grindstone-spindles, with a 
crank at one end, are open to the objection that the stone will 
never keep round, because every person is inclined, more or less, 
to follow the motion of his foot with his hand, which causes the 
pressure on the stone to be unequal. The harder pressure is al- 
ways applied to the very same part of the stone, and will soon 
make it uneven, so that it is impossible to grind a tool true. To 
avoid this, put in place of the crank a small cog-wheel to the 
spindle, say with twelve cogs ; have another short spindle, with 
a crank and a cog-wheel of thirteen cogs, to work into the former. 
The stone will make about 0.07 of a revolution more than the 
crank, and the harder pressure of the tool on the stone will change 
to another place at every turn ; and the stone will keep perfectly 
round if it is a good one. 

Grindstone, To true a carpenter's. — Use a f-inch bar of iron, 
or a gas-pipe, for a turning tool, held below the centre of the 
stone. 

Hardening, To prevent cracking of metals while. — Heat the 
water as hot as bearable to the hands, dip the metal endwise, and 
immerse with the thickest part of the metal downward. When 
fully immersed, hold the metal still until it is quite cold. 

Iron, Cast, To harden. — In 3 gallons of clean water, mix ^ pint 
oil of vitriol and 2 ozs. saltpetre. Heat the iron to a cherry- red, 
and dip as usual. 

Iron, Cast, Mixture for cast-iron cylinders, requiring to be 
hard. — Twenty pounds charcoal pig No. 5, 40 lbs. Scotch pig, 300 
lbs. scrap-iron. 

Iron, Cast, Mixture for strong and close-grained cast-iron for 
steam cylinders, etc. — Eighty pounds charcoal pig No. 5, 100 lbs. 
Scotch pig, and 100 lbs. scrap-iron. 

Iron, Malleable, Cast, To harden. — Mix equal parts of com- 
mon potash, saltpetre, and sulphate of zinc, and use as directed 
for prussiate of potash. 



MECHANICS. 45 

Iron Plate, To straighten a curved. — Hammer it lightly with 
a round pene-hammer on the hollow side. 

Iron Plates with true, flat surfaces. — To make a true surface- 
plate, it is necessary to plane up three plates, which we will 
term A, B, and C. First fit the faces of A and B together as 
nearly as possible with a smooth file (using a hardly perceptible 
coating of Venetian-red and common oil applied to A, to show by 
the marks where the faces touch). Then file C to fit A. Then 
try C with B ; and if they mark all over the faces, they are true, 
and the surfaces may be finished by the scraper, trying them re- 
peatedly as above. If, however, C and B should be found to fit 
on the edges only, it would demonstrate that A and B, though 
fitting, are not flat surfaces ; but that A is hollow and B round- 
ing. Having corrected these defects as nearly as possible, apply 
B to C, again repeating the correcting process until all three sur- 
faces, applied interchangeably, mark evenly all over, when the 
surface of each will be practically true. It must, however, be 
borne in mind that, after rubbing the surfaces together to test 
them, the middle of each plate will (from having received the 
most abrasion) show the marks the plainest, so that the plates 
will be more nearly true if the marks show a little the plainest 
at and near their edges, and less plain toward the centres. The 
back of each plate should be planed off, care being taken that it 
rests evenly upon the bench, so that neither plate shall deflect 
from its own weight, as it would do if its weight were not sup- 
ported evenly upon the face resting upon the bench. The scrap- 
er should be used dry upon cast-iron, and kept moistened with 
water for steel, wrought-iron, and brass. 

Iron, Red-hot, To mark measures on. — Blacksmiths fre- 
quently measure a piece of iron, and put chalk-marks where they 
desire to cut it. The iron may then be placed in the fire and 
heated to a bright red without effacing the marks. 

Iron, To remove hard skin from. — Hard skin on iron is due to 
heat and friction, and may be removed by heating to a dull red, 
filing the surface, and putting the iron to cool in lime or ashes. 

Iron, Wrought, Contraction of, — Wrought-iron may be made 
to contract to a slight extent by heating it to a low red heat, and 
quenching it in water. The first operation only, however, is ef- 
fective. This plan is used to shorten eccentric rods, etc., to avoid 
getting them out of true by upsetting them with blacksmiths' 
tools. 

Iron, Wrought, To close holes in. — If a washer or other 
piece of wrought-iron is a trifle too large, fill the hole and part of 
the outside faces with fire-clay ; heat the iron to a bright red, and 
plunge it in cold water. The contraction of the circumferential 
iron will squeeze the metal round the hole (which has been pre- 
vented from cooling so rapidly by the clay) inward, diminishing 
the size of the hole. To refit a bolt to a hole in which it has 
worn a trifle loose, case-harden it by the prussiate of potash pro- 
cess, which will increase the diameter of the bolt. If it fits into 
a hole of wrought-iron or steel, that too may be case-hardened, 
which will diminish its size, and thus refit it to the bolt. 



46 MECHANICS. 

Joints, Rubber. — In making a rubber joint, take a piece of 
clialk and rub it on the side of the rubber and flange where the 
joint is to open ; and when required, they will come apart easily, 
and not break the rubber, although the latter may be burnt and 
hard. Repeat the chalking before screwing up, and you will 
have as good a joint as ever, and the rubber can be used a great 
number of times. 

Keys, Driving. — Drive the key into the keyway to mark where 
it binds. The keyway should be oiled first, especially if the 
metal is cast-iron ; otherwise the surfaces are liable to seize a 
cut, making it very difficult to drive the keys out, and cutting 
ragged grooves in both the keyway and the key. The same 
rule applies to crank-pins and all similar work. 

Keys, To make. — These should be made to fit the key ways at a 
good fit on the sides without being tight, the locking being per- 
formed by the taper of the top and bottom, the amount of which 
should be about \ inch per foot of length. 

Keyway and Slots, To ease, when hardened. — Take a strip of 
copper and use it as a file, applying oil and fine emery upon the 
surface of the work. 

Lathe, Settinor work on the face-plate of a. — Let the work be 
set out and first lightly prick-punched ; then clamp to place light- 
ly as near as possible, but never set the *' dead-centre" against 
the work, for that will not bring it true ; now with a scratch- awl 
or sharp-pointed centre, with the point resting in the prick-mark, 
and the other end held against or on the dead centre, revolve the 
work. If the point marked for the centre of the hole is out of 
true, the scratch-awl, or whatever rests in the point, will vibrate. 
Put into the lathe-rest a tool, without fastening it, and push it 
up to the scratch as the work is revolved, and the extent of the 
vibration can be seen. The work can be driven as thus indicat- 
ed when there is no vibration of the scratch or centre, the work 
is perfectly set, and may be securely fastened. 

Liners, Thickness of. — To ascertain the proper thickness of a 
liner or strip necessary to go between a pair of brasses so that 
(when the faces do not meet) the liner may be placed between 
them and the brasses, when bolted up tight, without jamming 
the journal, place a piece of lead wire between the brasses, and 
then screw the cap down tight, and the lead wire will compress, 
denoting the necessary thickness of liner. The latter should be 
made a shade thicker than the distance the wire was compress- 
ed, so that the brasses may fit without binding the journal. 

Links, To close a quadrant or link that has sprung or opened in 
hardening. — Clamp it with bolts and plates, placing the die in the 
slot to support any part which does not require to be closed. To 
open the slot of a quadrant or link that has closed in being hardened : 
Take two keys having an equal amount of taper upon them, and 
place them together so that their outside edges are parallel. In- 
sert them in that part of the slot which requires to be opened, 
and holding a hammer against the head of one key on one side 
of the link, drive in the other key with a hammer on the other 
side of the link. After the key is driven as far in as the judg- 



MECHANICS. 47 

ment suggests, measure the width of the slot, so that, if the ope- 
ration was not performed to a sufficient extent on the first at- 
tempt, the operator may judge how much to essay at the second, 
and so on. To premnt, as far as possible, a slot link or quadrant 
from altering its shape in the process of hardening : Fit into the 
slot, at various parts along its length, pieces of iron of the same 
diameter as the die intended to work in the slot, and in quench- 
ing the quadrant, immerse it endwise and vertically. 

Nails into hard wood. To drive. — Dip in grease to assist pene- 
tration. 

Nuts, Tight, To ease. — To ease a nut that is a little too tight 
upon a bolt, place it upon the bolt, and, resting it upon an iron 
anvil or block, strike the upper side with a hammer, turning the 
nut so that not more than two blows will fall upon the same 
face. The smaller the nut, the lighter the blows should be, and 
vice versa. 

Nuts, Tight, To unscrew. — To start a nut that is corroded in its 
place, so that an ordinary wrench fails to move it, strike a few 
sharp blows upon its end face ; then holding a dull chisel across 
the chamfer of the nut, strike the chisel-head several sharp 
blows, which will, in a majority of cases, effect the object. 

Patterns, Cast-iron. — These should have their surfaces smooth- 
ed, and be then slightly heated and waxed all over with the best 
bees wax. 

Patterns for Brass Bed-Pieces. — In making a pattern for 
a brass bedding in a circular bed, first make the pattern at the 
same curve as the bed, and then pare off the centre of the crown- 
bed about ^ inch for every inch of diameter of bore of the brass ; 
the reasons for this are explained in treating of patterns for semi- 
octagonal bedding-brasses. 

Patterns for Brasses. — In making a pattern for a brass to 
fit in a semi-octagonal bed such as is employed in pillar-blocks, 
and sometimes in the small ends of connecting-rods and axle- 
boxes : after having made the bed of the brass to the same shape 
as the seat into which it beds, take off -^ inch in brasses be- 
low 3 inches bore, or \ inch in brasses above that size, from 
the crown face of the brass pattern, for the following reasons : 
The casting of iron or of brass contracts, in cooling, most at the 
sides, and the above is to compensate for this contraction. Fur- 
thermore, it will require only ^ inch to be cut off the angles to 
let a brass (having bed-angles at 40°) down ^ inch on the crown ; 
whereas it will require ^ inch taken off the crown face to let the 
bed-angles down xb^ inch. A strict observance of this rule will, in 
all cases, save one half the time required to fit such brasses to 
their places. In brasses whose bed-angles are more acute, a 
greater allowance must be made. 

Patterns, To fit. — To get a pattern to fit closely over an ir- 
regular casting having angles, projections, or crooks in it (such 
as is often required to make a casting with which to patch cylin- 
ders or junctions of pipes), take a piece of sheet-lead, and ham- 
mer it lightly with a round pene-hammer, closing it round the 
casting until it will, by stretching where it is requisite, conform 



48 MECHANICS. 

strictly to the shape of the surface, however irregular it may be. 
The moulder can then cast a patch from the sheet-lead, making 
ii of any required thickness. 

Patterns, Wooden. — These should never be left in the foun- 
dry, where they are liable to warp from the excessive range of 
temperature. 

Pening, Setting work by. — The operation termed " pening," is 
stretching the skin on one side of work to alter its shape, the 
principle of which is that, by striking the face of the metal 
with a hammer, the face of the metal struck stretches, and 
tends to force the work in a circular form, of which the 
part receiving the effect of the hammer is the outside 
circle or diameter. The engraving represents a piece of 



Q^ a 



flat iron, which would, if it were well hammered on the face, 
a a a, with the pene of a hammer, alter its form to that de- 
noted by the dotted lines. Or let the rod, a, shown below be 
attached to a double eye at one end, the other end requiring to 
come fair with the double eye, 6, at the other end ; then, if it is 
pened perpendicularly on the face, c, of the rod, the stretched 
skin will throw the end around so that it will come fair with the 



jLa 




eye, &. Connecting-rod straps which are a little too wide for the 
rod ends may be in like manner closed so as to fit by pening the 
outside of the crown end, or, if too narrow, may be opened by 
pening the inside of the crown end ; but in either case, the ends 
of the strap alter most in consequence of their lengths, and the 
strap will require refitting between its jaws. 

Pipes, Gas or Steam, Threads used in screwing : 

Inside diameter. Threads 
per inch. 

\ 27 

i 18 

f 18 

i 14 

1 IH 

li IH 

Taper of threads, i^ per inch of length. These inside diameters are 
only estimated, as they vary for pipes of different strength, the 



Inside diameter. 


Threads 




per inch. 


H 


IH 


2 


IH 


2i 


8 


3 


8 


3i 


8 


4 


8 



MECHANICS. 



49 



thickness varying for tlie different grades, and the outside diame- 
ter remaining the same. 

Piston-Rings, To open. — Hammer them lightly with a round 
pene-hammer all round their inside laces. 

PiSTON-ROD GrLANDS. — If these are rather tight, the piston-rod 
may be eased by rubbing the gland up and down the rod, and 
giving it at the same time a revolving motion back and forth at 
each stroke. Oil must be supplied to the rod to prevent the 
gland from seizing or cutting. A gland should be chucked in the 
lathe by the flange, so that the bore and outside diameter may be 
turned at one chucking, and thus be true without depending upon 
the truth of a mandrel. 

Plaster, Inserting screws in. — Make a large hole in the plas- 
ter and drive in a wooden plug, in which insert the screw. The 
plug may be first split and a groove cut in each half. 

Pulleys, Turning. — Pulleys should be turned either on a man- 
drel, or else chucked by the arms, since chucking them by the 
rims springs them out of true. 

Punching Metals. — The same elements of resistance enter 
into the operation of punching as in that of shearing. In short, 
a punch and die may be considered as shears with circular blades. 
The coeflBcient of pressure in punching, for any given area of 
section, will be exactly that for shearing the same area of sec- 




:i6r:^=-.^- 



SHRINKING METAL-WORK. 



tion, without reference to the thickness of the material. The 
measure of force necessary to effect the various punchings readi- 
ly gives the value of the resistance to shearing in cases of ordi- 
nary metals. This resistance, per square foot, is determined to 
be, in lbs. : For lead. 392,548 ; block-tin, 450,784 : alloy of lead 
and tin, 731,176; zinc, 1,843,136; copper, 4,082,941; iron, 103,- 
333. 



50 mechanics. 

Reducing the Size of Work by shrinking with Fire 
AND Water. — For reducing the size of wrouglit-iron work, the 
process shown in the following engraving may be employed. 
a a is the section of a wrouglit-iron square box or tube, which is 
supposed to be made red hot and placed suddenly in the water, 
B, from its end, C, to the point D ; the result is that the metal in 
the water, from C to D, contracts or shrinks in diameter, and com- 
presses the hot metal immediately above the water-line, as the 
small cone at D denotes. If then the box or tube is slowly im- 
mersed in the water, its form, when cold, will be as in the right- 
hand figure, that part from C to D maintaining its original size, 
and the remainder being smaller. 

It must then be reheated and suddenly immersed from the end, 
E, nearly to D, until it is cold, and then slowly lowered in the 
water, as before, which will contract the part from D to C, mak- 
ing the entire length parallel but smaller, both in diameter and 
bore, than before it was thus operated upon. 

Rolls, To prevent cinders getting between the necks of. — Bore 
grooves out of the bearings, 1^ inches wide and ^ inch deep and 
1^ inches apart, put them at an angle of 45° with the face of the 
brass, and fill up said grooves with soft Babbitt metal. Then 
when cinder or iron gets in, it will travel but a short distance be- 
fore it reaches the soft metal, and the motion of the roll will im- 
bed it therein so that it can not protrude and score the neck, as it 
would were it to stick in the brass. 

Rust, To remove, from small hollow castings. — Dip in dilute 
sulphuric acid 1 part commercial acid to 10 water ; wash in hot 
lime-water, and dry in the tumbler with dry sawdust. 

Sands and Facings for Castings. — For castings, such as 
pipes or small cylinders, fine sand, termed No. 1, is used, the fac- 
ing being plumbago. A good facing for loam castings is made of 
1 part Whitehead sand to 3 parts fire-sand. For very fine-faced 
castings, Albany or Waterford sand is unsurpassed. Another 
facing for fine castings is 1 part of sea-coal to 8 or 10 of Albany 
sand ; for heavy castings, however, 1 to 5 will answer. 

Saw-Blades, Small. — Mechanics who want small gig saw 
blades will find that the steel springs of which hoopskirts are 
formed will make capital ones of any lengths ; and they vary in 
width, so as to be suitable for a variety of uses. 

Screw-Drivers, The advantage of long. — The reason that a 
screw is driven more easily into wood by a long than by a short 
screw-driver, is that the tool is held at an angle, and consequently 
the long screw-driver affords a greater leverage than a short one. 
If both were secured so as to be at right angles to the face of the 
screw, there would be no difference in their action. 

Screws, To prevent, getting tight in their nuts. — Plane a key- 
way or groove in the screw, i in. wide, the full length of the 
screw and down to the bottom of the threads ; and it will act like 
a tap, and scrape all the hard gummy grease out of the. nut, and 
always keep it clean and working free. 

Screw and Brad Holes in finished work, To plug. — Glue 
the edge of the plug ; put no glue in the hole. By this means 



MECHANICS. 51 

the surplus glue is left on the surface, and if the plug does not 
hit the screw, it will seldom show. Set the heads of brads well 
in, then pass a sponge of hot water over them, filling the holes 
with hot water. This brings the wood more to its natural posi- 
tion, and closes by degrees over the head of the plug. When 
dry, sandpaper off and paint, and the putty will not hit the head 
of the brad. 

Screws, Hints about. — When screws are driven into soft wood 
and subjected to considerable strain, they are likely to work 
loose ; in such case, dip the screw in thick glue before inserting. 
When buying screws, see that the heads are round and well 
cut ; that there are no flaws in the body or thread part, and that 
they have gimlet points. A screw of good make will drive into 
oak as easy as others into pine, and will endure having twice the 
force brought against it. When there is an article of furniture 
to be hastily repaired, and no glue is handy, insert a stick a little 
less in size than the hole for the screw and fill the rest of ^he 
cavity with powdered resin ; heat the screw sufficiently to meet 
the resin as it is driven in. 

Screw, To remove. — An obdura-te screw may sometimes be 
drawn by applying a piece of red-hot iron to the head for a 
minute or two, and immediately using the screw-driver. 

Screw-Threads. — English and American proportions : 

The Whitworth Thread. 

Diameter in inches.... -i\ iAIi^iff -Jl 

Threads per inch 21 20 18 16 14 12 11 10 9 8 

Diameter in inches. ... li IJ 1| U If If 1| 2 2i 2i 
Threads per inch 7766554^4^44 

Diameter in inches... 2f 3 3i 3^ 3f 4 4i 4^ 4| 5 
Threads per inch 3^ 3i 3i 3i 3 3 2J 2| 2f 2f 

Diameter in inches 5i 5^ 5f 6 

Threads per inch 2| 2| 2i 2^ 

Angle of threads = 55°. Depth of threads = pitch of screws. 
(One sixth of the depth is rounded off at top and bottom.) 
Number of threads to the inch in square threads = ^ number 
of those in angular threads. 

Standard American Proportions. 

Diameter in inches i t^ I A i "re i f i 1 

Threads per inch 20 18 16 14 13 12 11 10 9 8 

Diameter in inches li li If H H If H 2 H ^i 

Threads per inch 7766 5155 4^4^4 

Diameter in inches.... 2f 3 3i 3i 3f 4 4i 4i 4f 5 

Threads per inch 4 3i 3i 3i 3 3 2f 2f 2f 2i 

Diameter in inches . . . 5i 5^ 5| 6 

Threads per inch 2i 2f 2f 2i 

Angle of threads = 60°. Flat surface at top and bottom = f of 
the pitch. For rough bolts, the distance between parallel sides 



52 MECHANICS. 



of bolt-head and nut = 1^ diameters of bolt + ^ of an incli. Thick- 
ness of head = ^ distance between parallel sides. Thickness of 
nut = diameter of bolt. In finished bolts, thickness of head = 
thickness of nut. Distance between parallel sides of a bolt-head 
and nut and thickness of nut is -j\- of an inch less for finished 
work than for rough. 

Softening Bright Work without damaging the Finish. — 
Place the pieces in an iron box, and fill in the interstices with 
iron turnings ; close the box, lute the cracks with fire-clay, and 
heat to a red, allowing the box to cool as slowly as possible. It 
is a good plan to let the furnace-fires go out and leave the box in 
the furnace to cool. 

Solder, To flow. — Ordinary solder, 2 parts tin and 1 part lead, 
will flow smoothly on tin when dipped by previously putting sal- 
ammoniac on the surface to be tinned. 

Spirit- Level, Accuracy of the. — The best length of bubble 
depends on the length or curvature of the tube, a short bubble 
being required for a tube with a small radius of curvature, and 
increasing regularly in proportion with the increase of the radius 
of curvature. 

Springs, Steel. — To find elasticity of a given steel-plate spring: 
Breadth of plate in inches multiplied by cube of the thickness in 
1^ in., and by number of plates. Divide cube of span in inches by 
product so found, and multiply by 1.66. Result, equal elasticity 
in -^ in. per ton of load. To find span due to a given elasticity and 
number and size of plate : Multiply elasticity in sixteenths per ton 
by breadth of plate in inches, and divide by cube of the thickness 
in inches, and by number of plates ; divide by 1.66, and find 
cube-root of quotient. Result, equal span in inches. To find num- 
ber of plates due to a given elasticity, span, and size of plates : 
Multiply the cube of the span in inches by 1.66. Multiply the 
elasticity in sixteenths by the breadth of the plate in inches, and 
by the cube of the thickness in sixteenths ; divide the former 
product by the latter. The quotient is the number of plates. 
To find the working strength of a given steel-plate spring : Mul- 
tiply the breadth of plate in inches by the square of the thick- 
ness in sixteenths, and by the number of plates. Multiply also 
the working span in inches by 11.3 ; divide the former product 
by the latter. Result, equal working strength in tons burden. 
To find span due to a given strength and number and size of plate : 
Multiply the breadth of plate in inches by the square of the 
thickness in sixteenths, and by the number of plates ; multiply 
also the strength in tons by 11.3 ; divide the former product by 
the latter. Result, equal working span in inches. To find the 
number of plates due to a given strength, span, and size of plate : 
Multiply the strength in tons by span in inches, and divide by 
11.3 ; multiply also the breadth of plate in inches by the square 
of the thickness in sixteenths ; divide the former product by the 
latter. Result, equal number of plates. The span is that due 
to the form of the spring loaded. Extra thick plates must be re- 
placed by an equivalent number of plates of the ruling thickness 



MECHANICS. 53 

before applying tlie rule. To find this, multiply the number of 
extra plates by the square of their thickness, and divide by the 
square of the ruling thickness ; conversely, the number of plates 
of the ruling thickness to be removed for a given number of 
extra plates may be found in the same way 

Springs, To reduce elasticity of, — A well-tempered bar-spring 
will lose much of its elastic strength by filing off a very thin 
scale from the surface. 

Steel, Advantage of holes punched in. — The advantage in 
tensile strength, when holes are drilled in steel rather than 
punched, is 25.5 per cent. 

Steel, Cast, To weld. — Apply powdered borax to .the weld 
while heating it in the fire. If the steel is made too hot, it will 
crack during the hammering process. 

Steel, Cast, Welding compound for. — Mix J lb. saltpetre and 
i lb. oil of vitriol in 2 gallons hard water ; heat the steel to a 
blood-red, and cool in the mixture before welding. Then reheat, 
in sand, and weld by hammering as usual. 

Steel, Fire for tempering. — In hardening and tempering steel, 
a clean charcoal, anthracite, or coked bituminous coal fire is re- 
quired ; such as is fit for taking a forging heat on iron is entirely 
unfit for hardening purposes. The sulphur contained in the 
coal combines with the steel to form sulphuret of iron, and ruins 
its texture. 

Steel, Tempering. — The colors shown at different temperatures 
Fahr. are as follows : Very pale yellowish, 430° ; pale straw, 
450° ; yellow, 470° ; brown, 490° ; mottled brown, 510° ; purple, 
530° ; bright blue, 550° ; blue, 560° ; dark blue, 600°. 

Steel, To demagnetize. — (1) Heat it to a red heat, and allow it 
to cool slowly. (2) Place the steel on a magnet, with the same 
poles touching the same poles of the magnet, and repeat the 
operation till total demagnetization has taken place. 

Steel, To remove blue color from. — (1) Use 1 part oil of vitriol 
to 10 parts water. (2) Dip the articles in a strong solution of 
cyanide of potassium nearly boiling. (3) Dip the article in hy- 
drochloric acid, and quickly rinse in clean water. 

Tempering steel for drilling rock.— Be careful not to overheat 
it in hardening and forging, and quench in salt water, drawing to 
a brown color. 

Tempering, The color-tests for.— Says Mr. J. Richards : '' Pro- 
cure eight pieces of cast-steel, about 2 in. long by 1 in. wide, 
and f of an inch thick ; heat them to a high red heat, and drop 
them into a salt-bath. Leave one without tempering, to show 
the white shade of extreme hardness, and grind off and polish 
one side of each of the remaining seven pieces. Then give them to 
an experienced tool-maker to be drawn to seven various shades of 
temper, ranging from the white piece to the dark blue color of 
soft steel. On the backs of these pieces paste labels, describing 
the technical name of the shades and the general uses to which 
tools of corresponding hardness are adapted. This will form an 



54 MECHANICS. 

interesting collection of specimens, and accustom the eye to the 
various tints, which will, after some experience, be instantly re- 
cognized when seen separately/* 

Tinning small castings. — Clean, and boil them with scraps of 
block-tin in a solution of cream of tartar. 

Water-wheel, Steps for. — No step or foot-bearing of metal is 
equal to one of good oak or rock-maple. 

Zinc, Stamping. — In stamping sheet-zinc in dies, much waste 
occurs from the small difference between the melting-point and 
the temperature at which sheet- zinc should be stamped to get the 
best effect. To obviate this waste, heat the zinc by dipping in 
oil at the proper temperature. 



ENGINEERING. 



TESTING THE STRENGTH OF MATERIALS 



BY PROF. R. H. THURST0:N^. 

The engraving wUich. accompanies this article illustrates a 
very convenient, yet quite accurate, method of determining- the 
strength of materials, which has been devised by the writer. 
The test-piece is made by cutting, from the piece of metal 
of which the strength is to be determined, a piece about 3 in. 




TESTING METALS. 



long and 1 in. square. At the middle of its length, a part is 
turned cylindrical in form and 1 in. long, with a diameter of i in. 
if of iron, or f in. if the metal is steel. The test-piece thus made 
is fastened in the vise, as shown in the engraving, and a long- 
handled wrench is attached to the projecting head. A spring- 



56 ENGINEERING. 

balance is secured to the end of this wrench, and the experimen- 
ter twists off the head by pulling on this sprinor-balance, as seen 
in the illustration. The balance should be capable of indicating 
weights of fifty pounds or more. By simply painting the scale 
of the balance with white-lead, or smearing it with tallow, and 
by springing the pointer so that it will touch the surface, a re- 
cording apparatus may be improvised which will indicate the 
maximum strain reached during the test. 

In testing, the experimenter pulls steadily on the balance, gra- 
dually increasing the force exerted, and watching carefully, and 
noting the action of, the test-piece and the balance, until fracture 
occurs. A resistance, which is apparently quite unyielding, is 
felt at first ; this is suddenly observed to be succeeded by a grad- 
ually increasing distortion of the test-piece, accompanied by an 
increasing resistance, up to the point of the commencement of 
rupture. From the latter point, the resistance becomes less and 
less, finally ceasing when the test-piece falls apart. By conduct- 
ing the operation very carefully, and noting resistances very accu- 
rately, all of the following important points may be determined : 

The limit of elasticity is the point at which the yielding first 
commences. Note the reading of the balance at this point and 
the angle of distortion. The last quantity is the measure of the 
stiffness of the metal. The most rigid pieces are, of course, those 
which yield the least with a given amount of force. After the 
piece has been twisted so far as to have taken a set, the pull may 
be relaxed, and the distance which the piece springs back is to be 
noted. The elasticity of the metal is measured by this recoil. 
The ductility of the metal is measured by the extent of yielding 
which occurs before fracture takes place. The resilience of the 
metal — which is the name given its power of resisting shock — is 
very closely proportioned to its strength multiplied by its ductili- 
ty. Therefore, to ascertain what blow would be resisted by it 
without its taking a set, it is simply necessary to multiply the re- 
sistance at the limit of elasticity by the amount of distortion ob- 
served within the elastic limit. The homogeneity of the material 
is indicated by the smoothness and regularity with which the 
metal changes in its power of resistance as the deformation pro- 
gresses. 

In making such a series of experiments, it is usually found 
best to first select a well-known and good brand of the kind of 
metal which it is proposed to test, and, by a set of experiments 
on test-pieces cut from it, to determine what, with the p'articular 
arrangement of apparatus chosen, is the resistance registered by 
the balance, and what are the characteristics of the metal as 
shown by the method here described. By a careful comparison 
of the behavior of the metal of which the quality is desired to be 
learned with this standard set of samples, the operator soon 
learns to judge quickly and accurately of the value of his mate- 
rial for any specified purpose. 

As the tensile strength of a metal is usually very closely pro- 
portional to the resistance to torsion, this also enables a very sa- 
tisfactory determination of the value of the metal for resisting 
tension to be obtained. In the autographic recording machine, 
built by the Mechanical Laboratory of the Stevens Institute of 



ENGINEERIKG. 57 

Technology, these results are permanently inscribed upon a sheet 
of profile-paper, the pencil of the a])paratus writing a diagram or 
curve which is a record of all the circumstances modifying the re- 
sisting power of the metal while under test. The rule being ap- 
plied, the torsional, and approximately the tensile, resistance is 
read off at a glance, and the position of the elastic limit, the ho- 
mogeneousness, the elasticity, the stiffness, the ductility, the 
resilience, are all found fully indicated by the diagram, and can 
be, at any subsequent period, shown by means of this automati- 
cally produced record. On these records, the tensile resistance is 
found to be about 25,000 pounds per square inch for each inch in 
height of the diagram. 

The peculiar method of fracture here adopted is well adapted 
to exhibit in the surfaces of the break any peculiarity of the 
metal. If homogeneous, it will show a uniform and characteris- 
tic fracture ; if seamy, it will be found to have cracks extending 
spirally around it ; if of cast-iron, the char, cter of the ruptured 
surfaces will at once reveal to the experienced eye whether the 
metal is fine or coarse grained, a dark foundry or a light forge 
iron, and Whether of close or open texture. If of steel, it will be 
readily seen whether it is '* high" or '* low," whether tool steel 
or of the machinery grade. Whatever the character of the ma- 
terial, the eye, experienced in such kinds of observation, will at 
once detect it, while the record of the experiment, or the " strain- 
diagram," will give the exact data of resistances, and will be a 
check upon the judgment thus formed. 



THE ENGINE AND ITS APPENDAGES. 

Condensers, Gain from the application of, to steam-engines. — 
In the early days of the steam-engine, very low pressure was or- 
dinarily employed for engines with condensers, while, on the con- 
trary, what was considered a very high pressure was adopted for 
engines that exhausted into the atmosphere. Hence arose the 
terms high and low pressure engines, the former being engines 
with, and the latter without, condensers. At present, a high 
pressure of steam is ordinarily carried in both kinds of engines, 
so that the terms do not describe the two varieties as well as 
formerly. Many engineers prefer to class engines as condensing 
and non-condensing, rather than as high and low pressure ; and 
this classification is generally considered the more correct of the 
two. One who regards economy puts in a condensing engine, 
if he has plenty of water in the locality ; and many old non-con- 
densing engines are being fitted with condensers, under the more 
enlightened engineering practice of the present time. 

It may be fairly assumed that a non-condensing engine has, on 
an average, at least 2 lbs. per square inch back pressure on the 
piston. By the application of a condenser, it might be expected 



«^8 EKGINEERING. 



that there would be a negative pressure of 10 lbs. per sq. inch on 
the back of the piston, so that the piston pressure would be in- 
creased by 12 lbs. In this assumption, an allowance is made for 
the power required to work the air-pump, and the engine is sup- 
j)osed to be at least 75 horse-power. For an engine smaller than 
this, it would be better to allow an increase in the positive pressure 
of not more than 10 lbs. per square inch. As the condenser, by 
decreasing the back pressure on the piston, adds just as much to 
the positive pressure, it is plain that a lower pressure of steam 
can be used, or the steam may be cut off at an earlier point of the 
stroke. The gain in either case can be approximately calculated. 
If the gain in positive pressure produced by the reduction in 
back pressure be multiplied by 100, and divided by the mean ef- 
fective pressure on the piston, it will give the percentage of gain 
in pressure due to the condenser. 

Thus, if the mean effective pressure on the piston is 30 lbs. per 
square inch, the gain in pressure will be 100 times 12, or 1200, 
divided by 30, which is 40 per cent. Now suppose that before 
the condenser was attached, the steam was cut off in the cylin- 
der at half stroke ; under the new conditions the required mean 
effective pressure can be obtained with a lower boiler pressure 
than before. Before the condenser was in use, it would be ne- 
cessary to maintain a pressure in the boiler of about 58 lbs. per 
square inch by gauge, to give a mean effective pressure of 30 lbs. 
on the piston ; while with an increase of 12 lbs. in the effective 
pressure, by the application of the condenser, a boiler pressure of 
about 39 lbs. would suffice. As the weight of steam per cubic 
foot at 58 lbs. pressure is 0.17481 lbs., and only 0.132 lbs. at 39 
lbs. pressure, there would be a saving of about 24.5 per cent in 
the amount of steam required to run the engine. Instead of re- 
ducing the steam pressure after attaching a condenser to an en- 
gine, it might be better to maintain the same pressure in the 
boiler, and cut off the steam at an earlier part of the stroke. In 
the case under consideration, the increase in 12 lbs. of the effec- 
tive pressure would permit of closing the steam port a little be- 
fore the completion of one third of the stroke ; and supposing 
that the clearance space in the cylinder amounts to 5 per cent of 
the capacity of the cylinder, the quantities of steam required per 
stroke, before and after the use of the condenser, would be in the 
ratio of 550 to 363, so that there would be a saving of 34 per 
cent. 

The example given represents a case in ordinary practice. By 
varying the data, of course a greater or less amount of saving 
would result ; but with an engine in good condition, it is gene- 
rally safe to estimate that a saving from 20 to 25 per cent of the 
amount of steam used, and, consequently, of the consumption of 
coal, will be realized by the application of a condenser. Indeed, 
it is not unusual for manufacturers to guarantee this amount of 
saving, in converting a non-condensing into a condensing engine. 

B. 

Cotton Machinery, Power required to drive. — The following 
are fair approximate rules : Cotton openers, 1 horse-power per 
1000 lbs. cotton delivered. Cotton pickers, 3 horse-power per 
1000 lbs. cotton delivered. Cotton cards, ^ horse-power per lb. 



cotton delivered per day, and, at 125 revolutions per minute, 0.12^ 
horse-power. Cotton cards, best practice, ^ horse-power per 
revolution per minute. Railway heads, breakers, 1 horse-power 
per each 10 yards per minute. Railway heads, finishers, 0.001 
horse-power per revolution per minute. Drawing-frames, 0.002 
horse-power per revolution per minute. Spindles, 0.005 horse- 
power per spindle per 1000 revolutions. Damp weather adds 
10 or 12 per cent ; methods of banding may make equally great 
variations. Looms require from 0.1 to 0.25 horse-power each. 
Pickers take 4 to 6 horse-power. Cloth shears from 3 to 4 horse- 
power. 

Cylinders, Balancing heavy. — The cylinder, being keyed upon 
its axle as it is intended to run, is lifted by a tackle or crane, and 
lowered so that each of its journals rests upon a stout steel 
straight-edge placed so that its upper surface is exactly level and 
parallel with its fellow. These straiglit -edges should not only be 
so rigid as to suffer no sensible deflection from the weight of the 
cylinder, but they should be very hard and smooth, and great 
care should be taken to keep them free from indentations. The 
journals of the cylinder must also be round and polished. The 
cylinder can now be loaded on its lighter side, or vice versa, until 
it will remain perfectly motionless when stopped in any part of 
its revolution. 

Cylinders, Locomotive, Placing in line. — To test the ac- 
curacy of the work after the bed-piece has been permanently fixed 
to the boiler, clamp a cylinder to its seat on the bed-piece, and fit 
a wooden cross (with a pin-hole through its centre) to the bore of 
the cylinder at its front end ; then pass a fine strong line through 
the hole, and extend it back so that it shall occupy a point ex- 
actly at the intersection of the central line of the driver-axle 
with the vertical plane of motion of the centre of the crank- pin 
and connecting-rod ; draw the line taut and fasten it in this posi- 
tion ; then apply callipers or a gauge at the rear end of the cylin- 
der, between the surface of the bore and the line, above and be- 
low and right and left of the line ; and if the cylinder is in line, 
the four distances will of course be exactly the same. It is essen- 
tial that the two horizontal distances should coincide exactly, and 
that the central lines of the two cylinders of a locomotive should 
be exactly parallel with each other, but for obvious reasons the 
exact coincidence of the two vertical distances is not essential to 
the efficiency or correct working of the engine. 

Instead of a wooden cross, as above mentioned, a more conve- 
nient instrument, made of metal, may be provided, consisting of 
four bevel gears. A, which serve also as nuts, which work lour 
sockets, B, with threads cut on their inner ends, all neatly fitted 
to a light casting, E, having a fine central hole for the line, as 
shown. A central gear, C, works the four gears, of course all at 
the same time. Several sets of steel rods, D, may be provided if 
necessary, of different lengths, and thus render the instrument 
universal in its application, each set of rods serving for cylinders 
varying two inches, more or less, in the diameters of their bores. 

To determine whether a cylinder of an old engine is in line : 
Remove the front head of the cylinder, the piston, the stuffing- 



60 



ENGINEERING. 



box gland, and the cross-head ; apply the cross and line, as above 
directed, extending the line through the piston-rod hole in the 
rear head to a point exactly central with the crank-pin when the 
crank is at its dead point ; draw the line taut, and, it the cylinder 




PLACING LOCOMOTIVE CYLINDERS IN LINE. 

is correctly in range, the line will occupy a central position in the 
stuffing-box, which may be determined as before directed. If the 
cross-head guides are parallel with the line, both vertically and 
laterally, they are also correct. 

Cylinders, Thick. — Thick cylinders are those in which the 
thickness is considerable in comparison with the internal diame- 
ter. To find the bursting pressure of a thick cylinder, take the pro- 
duct of (1) the tenacity of the material in pounds per square inch, 
and (2) the thickness of the cylinder in inches, and divide the pro- 
duct by the sum of (1) the thickness in inches, and (2) the internal 
radius of the cylinder in inches. Thus a cylinder with an internal 
radius of 4 inches, and a thickness of 5 inches, if made of cast- 
iron having a tensile strength of 16,000 lbs. per square inch, has 
a bursting pressure of 8888.9 lbs., this being the product of 
16,000 and 5, divided by the sum of 4 and 5. B. 

Engineer, Duties of the. — The ordinary daily duties of an en- 
gineer are as follows : On coming in the morning, he should first 
ascertain the amount of water in the boiler ; and, if that is all 
right, proceed to raise steam, either cleaning and spreading the 



ENGINEERING. 61 

fire, if it has been banked, or making it up, if it has been hauled. 
A fire is kindled in the boiler in essentially the same manner as 
in a stove, wood and shavings first being ignited, and then cover- 
ed with coal. In starting the fire, it is a good plan to cover the 
back of the grate with coal, to prevent the passage of cold air 
through the tubes. In getting up steam, the safety-valve should 
be raised a little, to permit the escape of air from the boiler. 
Having got the fire under way, the engineer should wipe off the 
engine, fill the oil-cups, and make any adjustments that may be 
necessary, such as tightening keys and screwing up joints or 
glands of stuffing-boxes, and should see that the cylinder-cocks 
are open. When steam is raised, he should open the stop*valve 
and start the engine ; after which, if a part of his duty is to at- 
tend to the shafting, he should examine and oil it. Then he 
should get out the ashes, provide a supply of coal, and screen it, 
if necessary, and proceed to make every thing tidy around the en- 
gine and boiler. Throughout the day, he should keep a watchful 
eye on the fire, the water, the steam, and the engine. In manag- 
ing the fire, care should be taken to have the furnace-door open 
as little as possible ; and, if steam is formed too rapidly, the fire 
should be regulated by closing the damper and ash-pit doors. In 
regulating the height of the water, it is a good plan to keep a 
steady feed, and maintain the height constant. If it is found 
that the water is falling, the engineer should discover whether it 
is caused by a leak, or by the refusal of the pump to work. He 
can tell whether the pump is working by the sound of the check- 
valve falling after each stroke, or by feeling the feed-pipe or 
check-valve. A pump will not feed when the temperature of the 
water is very high, unless it is specially adapted for pumping hot 
water ; and if it refuses to work from this cause, the temperature 
of the water should be reduced. A pump will not deliver water 
if the proper valves are not opened, if its passages are choked, or 
if its packing is defective. It would be necessary to examine the 
pump at once, and endeavor to discover and remedy the difficulty. 
If the water falls in the boiler on account of a leak, it can some- 
times be temporarily repaired with a plug, or the pump can be 
run faster, so as to keep up the water until stopping-time. If 
this is not possible, the fire should be hauled, and the engine al- 
lowed to run as long as there is sufficient steam -pressure. In case 
the engineer finds that the pump is not feeding, and he has a fair 
supply of water in the boiler, he should at once examine the pump, 
and endeavor to remedy the trouble without stopping the engine. 
If he does not succeed, however, before the water falls below the 
level of the lowest gauge-cock, he should haul the fire, and let the 
engine run as long as the steam-pressure is sufficient. If he has 
been called away from the boiler, and on his return finds that the 
water is below the level of the lower gauge-cock, he should imme- 
diately ascertain the steam-pressure, and if it is rising rapidly he 
should haul the fire at once. If the steam-pressure is about the 
same as usual, he should examine the pump ; and if it is not de- 
livering water, he should haul the fire. If the pump is feeding, 
he may run it faster, watching the steam-gauge carefully. If 
the pressure does not fall, he should stop the pump and haul the 
fire. In any case the engine should not be stopped until the steam- 



62 ENGINEERIN^G. 



pressure is considerably reduced. The engineer sliould be very 
particular, on finding the water low, to examine the steam-gauge 
at once ; and if the pressure is unusually high, he sliould haul 
the fire without delay. 

A boiler foams or primes either because it has insufficient 
steam room, or on account of dirt or grease in the boiler or the 
feed-water. The trouble is often experienced with new boilers, 
and disappears when they become clean. Priming is dangerous, 
if much water is carried over with the steam, as it is difficult to 
maintain the water-level constant, and the engine is liable to be 
broken by the water in the cylinders. If the trouble is caused 
by insufficient steam-room, it can sometimes be partially over- 
come by increasing the steam pressure, and throttling it down to 
the ordinary working pressure in the cylinder ; but the only ef- 
fectual way is to provide more steam-room. If the priming is 
due to dirt or grease in the boiler, the engineer should blow off" 
frequently, and clean the boiler every few days. In blowing off, 
it is well to raise the water-level in the boiler by putting on a. 
strong feed, and then blow down below the level that is ordi- 
narily maintained. It is very often the case that the water-level 
is higher when the engine is running than it is when none of 
the steam is being used. The engineer should ascertain how 
much higher the water rises in such a case, so as to have a pro- 
per quantity of water when the engine is stopped. B. 

Engine for a row-boat. — For an ordinary Whitehall row-boat, 
18 feet long, to run at a speed of 8 miles per hour, the engine 
should have two cylinders, 2 in. diameter and 3 in. stroke ; tubular 
boiler, 24 to 28 inches in diameter, 4 feet high ; propeller, 22 to 
24 inches in diameter, with 3 feet pitch. 

Engines and Boilers, Small. — By the aid of the accompany- 
ing table, the effective horse-power (that available for useful 
work) of small engines can be approximately determined. The 
table is designed for non-condensing engines, with cylinders up 
to 6 inches in diameter, and for piston-speeds up to 400 feet a mi- 
nute ; the connection of the engine with the boiler being sup- 
posed to be tolerably direct, the ports and pipes being of sufficient 
sizes, and the steam-valve closing when the piston has made 
three quarters of the stroke. As the table is designed for average 
conditions, it is evident that it will give results that are too large 
in some cases, and too small in others. 

I. — To find the horse-poioer of an engine corresponding to a given 
diameter of cylinder y length of stroke, number of revolutions per 
minute, and pressure of steam in the boiler. (1) Multiply the 
length of stroke in inches by the number of revol utions per minute, 
and divide the product by 6. The result is the piston-speed in 
feet per minute. (2) Find the number in the table the nearest 
to the given steam-pressure and calculated piston-speed, and 
multiply it by 0.7854 times the square of the diameter of the pis- 
ton in inches. Example : An engine has a cylinder 2 inches in 
diameter, and a lenfrth of stroke of 2 inches. It makes 400 revo- 
lutions a minute, and the boiler-pressure is 50 pounds per square 
inch. Ans.: Twice 400 is 800. 800 divided by 6 is 133^-, the piston- 
speed in feet per minute. (3) The nearest piston-speed in table 



ENGINEERING. 



63 



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64 



ENGlI^EERlNa. 



is 130 feet, and tlie number in table corresponding to speed of 100 
and pressure of 50, is 0.074 ; the number for speed of 30 and same 
pressure is 0.022 ; required number is sum of 0.074 and 0.022, or 
0.096, corresponding to speed of 130 and pressure of 50. The pro- 
duct of 4 and 0.7854 is 3.1416, and the product of 0.096 and 
3.1416, or the required horse-power, is 0.3-|-. 

IL— Diameter in inches of cylinder required for a gimn Iwrse- 
power, piston-speed, andhoiler-'pressure. (1) Find in the table the 
number nearest to the given piston-speed and steam-pressure. (2) 
Multiply the number obtained in (1) by 0.7854. (3) Divide the 
given horse-power by the quantity obtained in (2). (4) Take the 
square root of the quantity obtained in (3). 

Example.— Wh2X should be the diameter of cylinder of an 
engine developing 2 horse-power, with a piston-speed of 150 
feet a minute, and a boiler-pressure of 100 pounds per square 
inch V (1). The number from the table is the sum of 0.161 and 
081 or 0.242. (2) The product of 0.242 and 0.7854 is 0.1900668. 
(3) The quotient of 2 divided by 0.1900668, is about 10.5226. (4) 
The square root of 10.5226 is 3.24+, or about 3i inches, the re- 
quired diameter of cylinder. 

III. — The numher of pounds of water required to be evaporated per 
hour for each horse-power exerted, and for various hoiler-pressures, 
may he approximately estimated from the accompanying table. 
Pressure of Pounds of Pressure of Pounds of 



steam in 

boiler by 

gauge. 



10. 

15. 

20 

25 

30, 

40, 

50, 



water per 

effective 

horse-power 

per hour. 

118 

Ill 

105 

100 

93 

84 

79 



steam in 
boiler by- 
gauge. 



60. 

70. 

80. 

90, 
100, 
120, 
150 



water per 

effective 

horse-power 

per hour, 

75 

71 

68 

65 

63 

61 

58 



It is convenient, in calculations of the amount of water evapo- 
rated at various pressures and from various temperatures of feed, 
to reduce them to a common standard, namely, the equivalent 
amounts that would be changed into steam of atmospheric pres- 
sure, if the temperature of feed was 212° Fahrenheit ; or, as it is 
commonly called, to evaporation ''from and at 212°." Two 
tables are appended, for the purpose of facilitati nor this reduction. 
The second table is taken from Professor Rankine's ''Treatise 
on the Steam-Engine." 

Pressure and Temperature of Steam. 



Pressure 
by gauge. 

0... 
10... 
20... 
30... 
40... 
50... 



Temperature 
Fahrenheit. 

212« 

239° 

250° 

274° 

287° 

298° 



Pressure 
by gauge. 

60... 

70... 

80... 

90.. 
100... 
110.. 



Temperature 
Fahrenheit. 



307° 
,316° 
.324° 
.331° 
.338° 
.344° 



ENGINEEEIN^G. 



65 



Pressure 


Temperature 


Pressure 


Temperature 


by gauge. 


Fahrenheit. 


by gauge. 


Fahrenheit. 


120 


350° 


170 


375° 


130 


356° 


180 


379° 


140 


36r 


190 


384° 


150. ....... 


366" 


200 


,....388° 


160 


370° 





Factors of Evaporation. 



Tempe- 
rature 
of the 
steam. 


Temperature of the feed-water. 


32° 50° 1 68° 

i 


86° 


104° 


122° 


140° 158° 


176° 


194° 


212° 


212°. . . . 

230° 

248° 

266° 

284°. ... 

302° 

320°..... 

338° 

356° 

374° 

392° 

410° 


1.19 1.17 1.15' 1.13 

1.20 1.18 1.16^ 1.14 

1.20 1.18 1.16 1.14 

1.21 1.19 1.17 1.15 
1.211 1.20 1.18' 1.16 
1.22: 1.20 1.18 1.16 
1.221 1.21; 1.19; 1.17 

1.23, 1.21 1.1&; 1.17 
1.23; 1.22 1.20 1.18 

1.24, 1.22 1.20 1.18 
1.24i 1.23 1.21 1.19 
1.251 1.23i 1.22 1.20 

1 1 i 


1.11 
1.12 
1.13 
1.13 
1.14 
1.14 
1.15 
1.15 
1.16 
1.17 
1.17 
1.18 


1.10 
1.10 
1.11 
1.11 
1.12 
1.12 
1.13 
1.14 
1.14 
1.15 
1.15 
1.16 


1.08 
1.08 
1.09 
1.09 
1.10 
1.11 
1.11 
1.12 
1.32 
1.13 
1.13 
1.24 


1.06 
1.06 
1.07 
1.07 
1.08 
1.09 
1.09 
1.10 
1.10 
1.11 
l.ll 
1.12 


1.04 
1.04 
1.05 
1.06 
1.06 
1.07 
1.07 
1.08 
1.08 
1.09 
1.09 
1.10 


1.02 
1.02 
1.03 
1.04 
1.04 
1.05 
1.05 
1.06 
1.06 
1.07 
1.07 
1.08 


1.00 
1.01 
1.01 
1.02 
1.02 
1.03 
1.03 
1.04 
1.04 
1.05 
1.06 
1.06 



To illustrate the use of tlie tables, suppose an engine of 6 
liorse-power is supplied with steam at a pressure of 50 pounds 
per square inch, and that the temperature of the feed- water sup- 
plied to the boiler is 160°. It is required to find how much water 
must be evaporated per hour *' from and at 212°" for the engine. 
The temperature of steam having a pressure of 50 pounds is 298°. 
In the table of ** Factors of Evaporation/' the factor correspond- 
ing to a steam temperature of 302° and a feed temperature of 158° 
(which are the numbers in the table nearest to the given ones), 
is 1.09. Now this engine requires an evaporation of 6 times 79, 
or 474 pounds of water per hour, at a pressure of 50 pounds, or 
an equivalent evaporation '' from and at 212°'' of 1.09 times 474, 
which is equal to 516.66 pounds. 

lY. — To find the proportions suitable for a boiler which is to have 
a given evaporation, (a) To ascertain the grate-surface in square 
feet : Divide the number of pounds of water to be evaporated per 
hour, from and at 212°, by 75, for cylinder boilers ; by 77, for flue 
boilers ; by 78, for tubular boilers ; by 80, for locomotive and ver- 
tical boilers. 

Example. — Suppose that a cylinder boiler is to be proportioned 
for an evaporation of 500 lbs. of water per hour, at a pressure of 
75 lbs., the temperature of the feed- water being 80°. The equiva- 
lent evaporation will be 1.17 times 500, or 585 lbs., and the grate- 
surface 585 divided by 75, or 7-i% square feet. 

(&) To ascertain the heating surface in square feet : Multiply the 
grate-surface by 11, for cylinder boilers ; by 17, for flue boilers ; 
by 30, for tubular, locomotive, and vertical boilers, (c) To ascer- 
tain the cross-section of flues or tubes in square feet : Multiply the 
grate-surface by 0.134. This is an average value for good practice, 
and it can be varied between the limits of 0.125 and 0.143, as may 



66 ENGINEERING. 

be most convenient, {d) To ascertain the length of boiler : Cylin- 
der boilers should be from 10 to 13 times the diameter ; flue 
boilers from 5 to G times tlie diameter ; tubular boilers, and the 
shells of locomotive and vertical boilers, from 3 to 3^ times the 
diameter. There is very great variation from these figures in 
practice ; but the numbers given above represent the most gene- 
ral limits, so far as they can conveniently be classified. 

Examyle.— W\\sX are the dimensions of a tubular boiler for an 
engine that is to develop 4^ horse-power, with a steam-pressure of 
100 lbs., the temperature of the feed-water being 160° ? 

The equivalent evaporation required per horse-power per hour 
is 1.1 times 63, or 69t^(j lbs. The total equivalent evaporation is 
4i times 69-i%, or about 312 lbs. Hence the grate-surface, being 
the quotient arising from dividing 312 by 78, is 4 square feet. 
The heating surface is 30 times 4, or 120 square feet. The cross- 
section of the tubes should be about 0.536 square feet (4 times 
0.134), or it should vary between the limits of 0.5 (4 times 0.125) 
and 0.572 (4 times 0.143) square feet. 

While the rules relating to engines given above are generally 
only applicable for cases within the limits mentioned at the be- 
ginning of this article, those for the proportions of boilers give 
safe average values for the majority of cases that are met with 
in practice. B. 

Engines, Derangements of. — These are hot bearings, loose 
keys, and leaky joints. If a bearing heats continually, when 
properly adjusted and well lubricated, it is too small. Some- 
times bearings heat on account of dirt or grit, because they are 
set up too tightly, or are out of line. A hot bearing can often be 
cooled without stopping the engine, by mixing sulphur or black- 
lead with the oil, or by turning on a stream of water from a 
hose. If a joint blows out it can sometimes be wedged, so that 
the engine can be run until stopping time. An engineer should 
exercise all his ingenuity to overcome a difficulty without stop- 
ping the engine, except in cases where it would be dangerous to 
continue to run. If keys or bolts become loose, it will generally 
be indicated by a thump in the engine. To prevent the freezing of 
pipes and connections in exposed situations, they should either be 
thoroughly drained, or the water should be kept circulating in 
them. B. 

Exhaust Steam. — This should not be discharged into a brick 
chimney. It is liable to disintegrate the mortar and destroy the 
chimney. 

Steam-Engine Governors. — The ordinary pendulum governor 
consists of a vertical spindle, which is made to revolve by suitable 
mechanism, and carries, on opposite sides, a pair of arms, to 
which heavyweights are attached, forming revolving pendulums, 
which vary their positions at different speeds. The simplest 
form of construction is shown in Fig. 1, A B being the revolv- 
ing spindle, E and D the weights, secured to the spindle by rods 
jointed at G. Several positions of the balls are shown, corre- 
sponding to different speeds of rotation. In any of these posi- 
tions, the vertical distance, as G F, of the point of suspension, G, 
above the centres of the balls, is called the height of the governor ^ 



ENGINEERING. 



67 



and it can be found for any case by dividing 32,508 by the 
square of the number of revolutions per minute. For instance, 
if a governor makes 100 revolutions per minute, running with- 
out friction or other resistance, the vertical distance of the cen- 
tres of the balls below the point of suspension would be 32,508 
divided by 10,000 (the square of 100), or about 3i inches. A table 
is added, showing the heights corresponding to various speeds. 




Table. 



Revolutions Height in 

per minute. inches. 

10..... 352.08 

20 88.02 

30 39.12 

40 22.01 

50 14.08 

60 9.78 

70 7.184 

80 5.501 

90 4.347 

100 3.521 

125 2.253 

150 1.564 

175 1.150 

200 0.8802 

225 0.6955 

250 0.5633 



Revolutions Height in 

per minute. inches. 

275 0.4646 

300 0.3912 

350 0.2873 

400 0.2201 

450 0.1739 

500 0.1408 

550 0.1164 

600. 0.0978 

650 0.08333 

700 0.07184 

750 0.06259 

800 0.05501 

850 0.04873 

900 0.04347 

950 ....0.03901 

1000 0.03521 



68 EN"GINEERING. 

In practice, the pendulum governor is generally constructed 
somewhat as represented in Fig. 2, being connected to the con- 
trolling mechanism by short levers, so that a slight change in the 
position of the balls will move the regulator considerably. In 
estimating the height of the balls of such a governor, it is to be 
measured from E, where the centre lines of the arms produced 
cut the centre of the spindle. 

When a governor acts on the controlling mechanism of an en- 
gine, it encounters some resistance. There is also some friction 
of the moving parts, and a weight is ^sometimes added, either 
sliding on the sjiindle or connected to 'the spindle by a lever, in 
order to make the governor more sensitive. All these things in 
fluence the height of the governor. In a well-made instrument 
the friction is insignificant, and need not be regarded, but allow- 
ances must be made for the resistance, and the weight, if any is 
attached. Find how many pounds of force are required to move 
the controlling mechanism of the engine, and find the weight 




of the balls and of the attached weight, in pounds. Next de- 
termine how far the controlling mechanism is moved, and the 
attached weight raised or lowered, for a given change in the 
height of the governor-balls. Divide the distance moved by the 
resistance by the change in height of the balls in the same time, 
and multiply the quotient by the measure of the resistance in 
pounds ; divide also the vertical distance moved by the attached 
weight for a given change in the height of the balls, and multi- 
ply the quotient by this weight. Take the sum of these two pro- 
ducts and the weight of tlie governor-balls, and divide by the 
weight of the governor-balls ; multiply the quotient by the height 
for a governor working freely, taken from the table above : the 
quotient is the corrected height of the governor-balls. 

Example. — The two balls of a governor weigh 20 lbs.; the resis- 
tance of the mechanism is 10 lbs., and it moves 4 in. while the 
height of the balls changes i inch. The attached weight is 8 lbs., 
and it moves 2 inches vertically, while the height of tlie balls 
changes ^ in. What is the height of balls for a speed of 200 
revolutions a minute? Multiplying the quotient of 1 divided by ^ 
(4) by 10, the product is 40 ; multiplying the quotient of 2 divid- 



ENGINEERING. 69 

ed by J (8) by 8, tlie product is 64 ; dividing tbe sum of 40, 64, 
and 20 (124) by 20, the quotient is 6.2 ; multiplying 6.2 by 
0.8802 (the height for a free governor making 200 revolutions a 
minute), the product, the corrected height of the governor- balls, is 
about 5^ inches. 

In designing a governor, it is well to fix upon some range of 
speeds between which it shall control the engine, and make the 
balls heavy enough to effect this. The proper weight for the 
balls can be found approximately, as below: 

(1) Divide the distance through which the resistance moves by 
• the change in height of the governor-balls in the same time, and 

multiply the quotient by the resistance ; divide the vertical dis- 
tance through which the attached weight moves by the vertical 
distance moved by the balls in the same time, and multiply the 
quotient by this attached weight ; add together these two pro- 
ducts, and divide the sum by 2. 

(2) Subtract the mean speed of the governor from the greatest 
speed it is to have, and divide the difference by the mean speed ; 
divide the quantity obtained in (1) by this quotient : the result 
will be the weight of the two balls. 

Example. — Suppose the resistance and attached weight are the 
same as in the preceding example, and that the speed of the 
governor is to vary between 200 and 300 revolutions a minute, in 
controlling the speed of the engine. What should be the weight 
of the balls ? 

(1) The sum of 40 and 64 (the corrected resistance and attached 
weight) is 104 ; i of 104 is 52. 

(2) The difference between 300 and 200 (100), divided by 200, is 
0.5 ; the quotient of 52 divided by 0.5, or the weight of the balls y 
is 104 lbs., so that each ball must weigh 52 lbs. B. 

Horse-power, Different kinds of. — In making an estimate or 
measure of the effect of any piece of mechanism that is used to 
overcome resistance, it is necessary to have a unit of reference. 
In whatever manner the resistance is overcome, if it can be mea- 
sured it can be converted into the amount of work that must be 
expended to raise a weight through a distance, since by suitable 
arrangements the mechanism can be put in motion and made to 
overcome resistance by allowing the weight to fall. This gives a 
simple mode of estimating the work, by assuming that a unit of 
work is the amount required to raise 1 pound a distance of 1 foot 
vertically. To illustrate, suppose that a cut is being taken from a 
6-in. shaft in a lathe, and that the resistance to the motion of the 
cutting-tool is 200 lbs. ; how many units of work are performed 
each time the shaft makes a revolution ? 

In each revolution of the shaft, the tool makes a cut 6 times 
3.1416, or 18.8496 ins., or 1.5708 ft. in length, and the work is 
the same as would be required to raise a weight of 200 lbs. 
through a vertical distance of 1.5708 ft., or it is 314.16 units. 

Now, if 33,000 uuits of work are performed in a minute, they 
constitute ^unit of power, known as a Jiorse-power^&nd con- 
versely, a horse-power can be defined as the power required to 
raise 33,000 lbs. 1 ft. high, or do 33,000 units of work in a 
minute. Again, a horse-power may be defined as the power re- 
quired to perform 550 units of work in a second, or 1,980,000 



70 ENGINEERING. 

units in an hour. To apply the principle to the example given 
above, suppose the shaft makes 20 revolutions a minute, how 
many hortie- power are required to drive the tool? In this case, 
the units of work performed per minute would be 20 times 
314.16, or 6283.2, and the horse-power would be TJTom) oi 6283.2, or 
about 1^1)- of ^ horse-power. It will be seen, from this e ample, 
that if the resistance to motion in pounds and the speed of motion 
in feet per minute can be measured, it is only necessary to multi- 
ply them together, and divide by 33,000, in order to obtain the 
horse-power. The steam-engine is a machine that is commonly 
rated as being of a certain horse-power, but the term horsepower, 
as thus used, does not always have the same meaning. In fact, 
there are four kinds of horse-power by which an engine may be 
rated : 

1. Gross or indicated horse-power. 

2. I^et or effective " 

3. Total 

4. Nominal " 

1. The gross or indicated horse-power of an engine is the power 
calculated by assuming the resistance to be that due to the mean 
effective pressure of the steam on the piston, as shown by the in- 
dicator. Thus, suppose this pressure is 2500 lbs., and the piston 
moves 400 ft. a minute, the gross horse-power is 400 times 2500 
divided by 33,000, or 30.3. 

2. The net or effective horse-power of an engine is computed 
from the useful resistance overconie. If, in the preceding exam- 
ple, the pressure on the piston, after deducting that required to 
overcome the friction of the engine, is 2200 lbs., the effective 
horse-power is 2200 times 400, divided by 33,000, or 26.7. 

The net horse-power is the proper kind to be specified by a 
steam-user when he is buying an engine. 

3. The total horse-power of an engine is computed from the to- 
tal pressure of the piston above a vacuum. If, in the example 
given in Case 1, the total pressure on the piston is 4200 lbs., the 
total horse-power is 400 times 4200, divided by 33,000, or 50.9. 

Total horse-power is only used in comparisons of the results of 
experiments. 

4. The nominal horse-power of an engine has no meaning in 
particular — that is to say, there are a number of different rules 
by which it may be computed. Thus, there is the admiralty rule 
for marine engines, Mr. Bourne's rule for condensing engines, 
Mr. Bourne's rule for non-condensing engines, James Watt's rule ; 
and numerous engine-builders have private rules of their own. 
For instance, A says, " I will make an engine with a cylinder 10 
ins. in diameter, and a stroke of 15 ins., and I will call it 8 
horse-power, nominal." 

B, who builds an engine of the same size, and wants to make 
purchasers think they are getting more for their money, says, 
" I will call my engine 16 horse-power, nominal." The man who 
goes to buy a steam-engine of either of these parties may very 
properly say to them, *' How much will you charge me for an 
engine guaranteed to be of so many horse-power, actual ?" B. 

Indicator, The steam-engine. — The construction is shown in 
Figs. 1 and 2, Fig. 1 being an elevation, and Fig. 2 a section. 



ENGINEERING. 



71 



The indicator is a recording steam-gauge, very accurately made, 
for determining the pressure acting on the piston of an engine, 
at every point of the stroke. It is connected to the cylinder, 
close to one end, and when the cock, seen in Fig. 1, is opened, 
the steam presses on a small piston, shown in Fig. 2. A stiff 
spiral spring above this piston is compressed by the pressure of 
the steam. The piston-rod, it will be seen, is connected to a 
lever, and this, in turn, with a link and another lever, a pencil or 
marking-point being placed in a hole in the link. There is a 
cylindrical barrel to the left on which a piece of paper can be 
placed, being held by two clip springs. This barrel can be made 
to revolve by pulling a string wound round the bottom, and it 
has within it a coiled spring, which makes it turn back again 




Fig. 1. 

the indicator. 



Fia. 2. 



when the tension of the string is relaxed. Now, suppose that the 
indicator is attached to the cylinder of an engine, and the cord is 
fastened to some moving part, so that when the engine makes a 
stroke it causes the barrel carrying the paper to revolve, and on 
the return stroke the coiled spring in this paper barrel makes it 
turn back to its original position. Meanwhile the steam in the 
cylinder is pressing on the piston of the indicator, forcing it up 
a distance corresponding to the pressure, so that if the pencil is 
allowed to touch the paper, it will trace out a line which repre- 
sents the pressure, and this line is called an indicator diagram. 
Such a diagram is shown in Fig. 7. The atmospheric line, G i>, 



72 



ENGINEERING. 



is traced when the cock is closed and there is no pressure on the 
piston. At h, the stroke of the engine commences, and when the 
piston has gone about half way to the other end of the cylinder, 
the steam is cut off, as shown at c, and the pressure begins to fall 
as the steam expands. Near the end of the stroke, the exhaust- 
valve opens, as shown at d, and the pressure falls more rapidly. 
When the engine makes the return stroke, there is only the back 
pressure, until near the end, when the exhaust- valve closes, 
shown at /, and the steam being compressed, the pressure rises. 
Just before the end of the stroke, at a, on the diagram, steam is 
admitted, and the pressure rises suddenly. 

I. How to attach the indicator to the cylinder of an engine. 
Drill a hole in the cylinder, in the head, or close to the end, 

and tap it out for a half-inch iron nipple. The indicator-cock 
must be connected to this, using an elbow, if necessary, and then 
the indicator can be attached at pleasure. In drilling this hole, 
do not make it close to the ports. Sometimes the connections 
from the two ends of a cylinder are brought together, and one 
indicator is made to answer for both ends, a cock being fitted in 
each pipe, so that either can be opened to the indicator, as desired. 
In such a case, the holes in the cylinder should be larger, for 
three-quarter inch pipe, at least, so as to prevent any loss of pres- 
sure. It is obvious, however, that as the indicator is used to ob- 
tain the pressure in a cylinder, the more closely and directly it is 
connected, the better. 

II. How to make the paper barrel have a motion coincident with 
that of the pidon. 

a. Beduciny -wheel— Fig. 3. 




This is attached to some part of the engine-frame, and the cord 
marked " to engine" is made fast to the cross-head, being carried 
over a pulley, if necessary, so that it is parallel to the guides. The 
other cord is fastened to the cord wound round the paper barrel of 
the indicator. The two wheels bear the same proportion to each 
other as the stroke of the engine does to the desired range of 
motion for the paper barrel, the latter being usually from 4 to 



ENGINEERING. 



73 



5 mclies. There is a coiled spring in tlie reducing- wheel, which 
makes it turn back on the return movement of the cross-head. 
By having different sized wheels to carry the cord leading to the 
indicator, this arrangement can be adapted to engines with dif- 
ferent strokes. 
6. Smnging-board, with slot — Fig. 4. 




Mark a point, A, at some convenient distance from the cross- 
head, and on a line perpendicular to the guides, at the centre of 
the stroke. Attach a board so that it can swing freely around 
this point ; cut a slot in the other end, for a pin connected to the 
cross-head. Then, as the cross-head moves, it will make the 
board swing to and fro. At some point B, of the board , which 




has the proper movement for the paper cylinder, attach a cord or 
wire, and carry it over a pulley, (7, adjusted at such a height that 
the part of the cord, B C, is parallel to the guides when the en- 
gine is at half stroke. The cord can then be brought down and 
attached to the cord of the paper barrel. 



74 ENGINEERING. 

c. Swinging-board, with link. — Fig. 5. 

Sometimes it is not practicable to attach the board directly to 
the cross-head by a pin, and it is more convenient to use a link 
connection, the arrangement of which will be evident from the 
figure. 

It is easy to see that a number of arrangements could be de- 
vised on the general principle of the swinging-board. Sometimes 
it is attached to the guides by a standard, and sometimes one end 
is connected to the cross-head and the other to the indicator, the 
point around which the board swings being between, at distances 
from the two ends proportional to the stroke of the engine and the 
movement of the paper barrel. Whatever the special arrange- 
ment, attention should be given to these two points : 

1st. To have the board perpendicular to the guides when the en- 
gine is at half stroke. 

2d. To lead the cord off in a direction parallel to the guides. 

III. How to take an indicator diagram. 

If a cord is used for the motion, it should have a slide on it, so 
that it can be adjusted, and it should have a hook so that it can 
be attached to the cord of the paper barrel, and detached at 
pleasure. Fine wire is better than cord, as it is quite flexible, 
and does not stretch so readily. If several cards, taken at inter- 
vals, are of the same length, the connection is all right. Having 
got the motion properly adjusted, turn the cock of the indicator 
so that it will blow through, having first put a piece of paper on 
the paper barrel. Then turn the cock so as to let steam into the 
indicator, and press the pencil lightly against the paper ; draw it 
back as soon as the card is traced, shut the indicator-cock, and 
apply the pencil again, to trace the atmospheric line — be par- 
ticular not to trace the atmospheric line until the diagram is 
taken ; then unhook the cord, remove the diagram from the 
paper cylinder, and mark on it the pressure of steam by gauge, 
the revolutions per minute, the height of the barometer, and the 
temperature of the engine-room — if the proper instruments are 
available — and the vacuum by gauge, the temperature of the 
hot- well, and the temperature of the injection- water, if the dia- 
gram has been taken from a condensing-engine. All the dimen- 
sions of the engine should also be noted, for future reference, to- 
gether with such particulars in regard to the dimensions and per- 
formance of the boiler as can be obtained. 

A counter should always be employed to determine the number 
of revolutions per minute, at the time the diagram is taken. It 
can be connected to the indicator motion, or to some moving part 
of the engine. Take its reading at the beginning of a minute, 
and at the end, having indicated the engine meanwhile. This 
gives the revolutions at the time the card was taken, with consid- 
erable accuracy. 

IV. HoiD to draw the true diagram. — Fig. 6. • 

The indicator diagram from one end of the cylinder, it is evi- 
dent, only shows what takes place on the side of the piston on 
which the indicator is applied — but at the same time tliere is 
some back pressure on the other side, opposing the motion of the 



ENGINEERING. 



75 



piston. To get tlie actual diagram, therefore, it is necessary to 
take diagrams from both ends of the cylinder simultaneously, 'and 
then combine the parts of each that were traced at the same time. 
Thus such a figure as is shown in Fig. 6 is obtained. On one 
side of the piston, the line ab c f Ib traced, and d c eis traced at 




the same time on the other, and the figure so obtained is the true 
diagram representing the distribution of the pressure. In using 
the diagram as ordinarily taken, therefore, the actual effective 
pressure is not obtained ; but there is no error in practice, since 
the inaccuracies of the diagrams from the two sides balance each 
other. It is a great mistake, however, to take diagrams from one 
end of a cylinder only, and assume that those from the other 
would be similar. Quite often there are serious differences, and 
both ends of a cylinder should always be indicated, if possible 

V. How to ascertain the mean effective pressure from a diagram. 
—Fig. 7, 




9 



5? ^ ^ 



fc^ 



vJ- 



2? 



^ 



J^y, 



er*T^ 



a. \st method. — Draw perpendiculars to the atmospheric 
line, from the extremities of the diagram, thus determining 
its length, C D ; divide the line, (J D, into 10 equal parts, 
and midway between each of the divisions erect a perpendicular, 
to G D, drawing it between the upper and lower boundaries of 
the diagram ; measure the length of each of these lines on the 
scale of the indicator-spring, add the measurements together, 
and divide the sum by 10. In the figure, the pressure, or length 



76 



ENGINEERING. 



of the line on tlie scale, is shown at each perpendicular. The 
sum of these is 363, so that the mean effective pressure is 36.3 
lbs. per square inch. 

h. 2d method. — Draw perpendiculars between the ten divisions 
of G D, as explained above. Then take a strip of paper, apply 
\l to the first perpendicular, and mark the length ; apply it to the 
next perpendicular, and mark its length, next to the first ; so 
continue applying it to each, and when the last perpendicular lias 
been measured, the distance between the first and last marks will 
be the sum of all the lengths. The strip of paper, A B, is shown 
in the figure as applied to the third perpendicular. Measure the 
length of the paper between the extreme marks, in inches, multi- 
ply it by the scale of the indicator-spring, and divide by 10. Sup- 
pose, in the present case, that the length of the paper is found to 
be 12.1 inches, and that each inch represents 30 lbs. on the scale 
of the indicator- spring ; 30 times 12.1 is 363, so that the mean 
effective pressure is 36.3 lbs. per square inch, as before. 

c. Positive and negative pressure. — Fig. 8. 




When the steam is cut off very early in the stroke, and the 
valves and piston are tight, a diagram is sometimes drawn 
like that in the figure, in which the back pressure is greater than 
the forward pressure for a portion of the stroke, and the pressure 
determined from the portion of the diagram a cl) must be sub- 
tracted from the pressure due to the portion deaf. In such a 
case, the method of determining the mean pressure is as follows : 
Divide the atmospheric line into 10 equal parts, as before, and 
draw perpendiculars midway between them ; add together the 
perpendiculars (measured in the scale of the indicator-spring) in 
the positive part of the diagram, also those in the negative part ; 
subtract the latter from the first sum, and divide the difference by 
10. In the figure, the pressures at the different perpendiculars are 
given. The sum of the positive pressures is 179, of the nes^ative 
pressures 25, and the difference is 154 ; so that the mean effective 
pressure is 15.4 lbs. per square inch. 

VI. How to find the indicated horse-power of a steam-engine. 

Having determined the mean effective pressure from a diagram, 
by one of the methods explained above, multiply this pressure by 
the product of the stroke in feet, the square of the diameter of 



ENGINEEKHS-G. 



77 



the cylinder in inclies, the number of revolutions per minute, and 
0.0000476. 

Example. — Suppose the mean effective pressure is 50 lbs. per 
square inch, the diameter of the cylinder 15 inches, the length of 
stroke 2 feet, and the number of revolutions per minute 80. 
Then the horse-power is the product of 50,225 (the square of 15), 
80, and 0.0000476, or 85.68. 

VII, How to construct the theoretical diagram. — Fig. 9. 

-— ^ 




This is the diagram that would be taken if the steam acted in 
the cylinder with the pressure at the beginning of the stroke un- 
til the point of cut-off, and that then the admission ceased instan- 
taneously, and the steam expanded, in accordance with Mariotte's 
law, to the end of the stroke, when the exhaust- valve opened, and 
the steam was immediately condensed, creating a perfect vacuum 
in the cylinder for the return stroke. Such a diagram is repre- 
sented \>j A B G D E, this being the theoretical diairram for the 
actual diaorram, ah c d e. The following is the method of laying 
it down: Draw a line, E D, 2Lt a distance below the atmospheric 
line, n d, equal to the pressure of the atmosphere (14.7 lbs. per 
square inch on an average), on the scale of the diagram ; mark 
on E D the length, o D, of the actual diagram ; then find the to- 
tal volume of the clearance spaces at the end of the cylinder from 
which the diagram was taken, and make o E bear the same rela- 
tion to D 3ls this volume of clearance has to the total volunie 
swept through by the piston per stroke. • To make this plain, sup- 
pose that in a cylinder having a diameter of 24 inches and a stroke 
of 3 feet, it is found that the volume of the clearance spaces at one 
end of the cylinder is 900 cubic inches. The volume swept through 
by the piston per stroke is the product of 0.7854, 24 squared, and 
36 or 17,286 cubic inches, so that the clearance is about y^fo of the 
piston displacement, and o E must be made ilwo ^s long" as o D. 
Thus, if (? i) is 5 inches, o E must be -^^ of an inch. Having de- 
termined the point E, make E A perpendicular to E By and draw 
a line, A B, parallel to E B, at such a height that it represents 
the initial pressure of the steam. Through c, on the actual dia- 



7 8 ENGINEERING. 



gram, wliere the steam is cut off, draw a perpendicular, B H, to 
E D. Divide E B into any number of equal parts, and erect per- 
pendiculars at tlie points of division that are beyond the point of 
cut-oflF. From E draw any diagonal line, E F, and from ^ as a 
centre, with a radius E H, draw an arc cutting E F in the point 
G. From the same centre, and with radii equal to E 4:, E 5, etc., 
draw arcs cutting E F. The arc drawn with a radius E 4, cuts 
E Fin the point /. Draw the line f A, and from G draw a line, 
G g, parallel to f A. From g draw a line, ^.7^, parallel to /J., 
and the point li, in which it cuts the perpendicular drav^^n through 
4, is a point of the curve of expansion. The construction of the 
points on the other perpendiculars is precisely similar, and is in- 
dicated in the figure. Having determined a sufficient number of 
points, draw through them the curve of expansion, B h i k I m (7, 
and the theoretical diagram will be completed. 

This kind of diagram is useful for comparing the merits of dif- 
ferent engines, since it is evident that, other things being equal, 
the engine whose actual diagram most closely approaches the 
theoretical is the best. The mean pressure, as shown by such a 
diagram, can be determined by one of the methods already ex- 
plained, for comparison with the pressure given by the actual 
diagram. 

VIII. How to take care of the indicator. — Always oil the cylinder 
and all moving parts before applying the instrument to an engine. 
Never use any thing but the finest grade of oil, such as that 
specially prepared for sewing-machines or clocks. After taking 
one or two diagrams, remove the indicator, and examine its steam- 
cylinder. If any grit has entered, wipe it out, using soft cotton- 
waste on the end of a white-pine stick. It is important to attend to 
this on indicatino^ an engine of which the condition is not known, 
and if it is found that dirt or grit is forced into the indicator, it 
should be cleaned at frequent intervals during the experiments. 
As soon as the experiments have been concluded, remove the indi- 
cator, and when it has cooled sufficiently, wipe it out and apply 
oil in the steam cylinder, and to all the moving parts. Be careful 
to dry the spring thoroughly, and cover it with oil. Never put 
any hard substance into the steam-cylinder, but use a white-pine 
stick and soft cotton-waste. After use, take out the plug of the 
indicator-cock, clean it and the seat, apply oil, and on replacing it 
adjust it so that it moves freely and does not leak. 

It might be supposed that minute directions of this kind were 
superfluous, and that any one owning an indicator would see the 
necessity of using such a delicate instrument with great care. 
The generality of the indicators in common use, however, im- 
press the observer with the idea that all the directions recited 
above have been studiously neglected B. 

Slide- Valves, Setting. — The methods of adjusting the lap 
«nd travel of slide-valves, and the position of the eccentric, given 
below, are taken, with some slight modifications, from the work 
of Dr. Zeuner, on Slide -Valve (bearing. It is believed that the 
simplicity of the construction will be appreciated by the reader. 



ENGINEERING. 



79 



I. Area of ports. — To find the proper area of port for an en- 
gine of a given piston-speed, multiply the area of the piston, 



^ 




SETTING THE SLIDE-VALVE. 



in square inches, by the number nearest to the given piston-speed 
In the table on the next page. 



80 ENGINEEEING. 



Speed of piston, in feet, 


Number by which area of piston 


per minute. 


is to be multiplied. 


100 


0.02 


200 


0.04 


300 


0.06 


400 


0.07 


500 


0.09 


600 


0.1 


700 


0.12 


800 


0.14 


900 


0.15 


1000 


0.17 


1100 


0.19 


1200 


0.2 


1300 


0.22 


1400 


0.24 


1500 


0.25 



II. Lap, lead, and tra'Gel of valve. — The amount of opening 
given by tlie valve for the admission of steam or its exhaust, at 
the commencement or termination, respectively, of the stroke of 
an engine, is called the lead, either steam or exhaust, as the case 
may be. If the face of the valve is wider than the port, the ex- 
cess of width is called lap, and may be either steam or exhaust 
lap. Steam-lap is an excess of width on the outer extremities of 
the valve-faces, and exhaust-lap an excess on the inner faces. 
The effect of steam lap is to cut off the steam at an earlier point 
of the stroke, and exhaust-lap causes the exhaust to open later 
and close earlier than it otherwise would. It must be obvious 
that the action of the exhaust would be very much deranged if 
an attempt was made to cut off very short, and it is found, in 
practice, that the limiting point of cut-off with the simple slide- 
valve is at about two thirds of the stroke. 

The travel of the valve is the distance between its two extreme 
positions. For a valve without lap or lead, the travel is equal to 
twice the width of the steam-port. If lap is added, the travel of 
the valve is equal to twice the width of the port, increased by 
twice the amount of steam-lap on one end. 

III. The eccentric. — The eccentric, which moves the valve, is a 
substitute for the crank, and consists of a circular disk secured to 
the shaft, the centre of the disk lying outside of the centre of the 
shaft. The distance between the centres of the eccentric and the 
shaft is equal to half the travel of the valve. If a valve has 
neither lap nor lead, the eccentric is secured to the shaft in such 
a position that a line joining its centre with the centre of a shaft 
is perpendicular to a line connecting the centre of the shaft and 
the centre of the crank-pin. If the valve has lead, the eccentric 
must be turned on the shaft sufficiently to secure the desired 
amount, and if lap is also added to the steam side, the eccentric 
.must be advanced still further. In either of these cases, the 
amount the eccentric is moved forward is termed the angular ad- 
vance of the eccentric, being the angle made by a line joining 
tlie centres of the eccentric and shaft with a line dravv^ through 
the centre of the shaft perpendicular to the line of centres of the 



e:n^gineerikg. 81 

crank-pin and shaft. The points in which these two perpendicu- 
lar lines intersect the shaft should be plainly marked by a 
centre-punch or chisel, for convenience in adjusting the eccentric. 

IV. Proportions of valve and seat.— The bridge of the valve- 
seat should generally have a width equal to the thickness of the 
cylinder. The width of the exhaust-port is found by adding the 
width of the steam-port to the half -travel of the valve, and sub- 
tracting the width of the bridge. 

The length of the valve is equal to the width of the exhaust- 
port, increased by the width of the bridges and the two faces. 

V. To find the lap and travel of the valve, and angular ad- 
vance of the eccentric, for given points of admission, cut-off, and 
release. — Draw a horizontal line, A B, and lay off on it, any dis- 
tance, A C, to represent the length of stroke of the engine. Make 
E S equal to the length of the connecting-rod between centres, 
and 8 D equal to one half of A C. With i> as a centre, and D 8 
as a radius, describe a circle, which represents the path described 
by the centre of the crank-pin. The arrow shows the assumed 
direction of the motion of the engine. Assume some point, E, at 
which it is desired to have the steam-valve betrin to open when 
the piston has still to complete the portion E A oi its return 
stroke. Assume also a point, F, at which the steam is to be cut 
off when the piston has advanced a distance, E F, and a point, G, 
at which the exhaust- valve is to be begin to open when the pis- 
ton has completed the portion E G of the stroke. Then, with 
each of these points, E, F, G, as a centre, and with the length of 
connecting-rod, A 8, as a radius, describe an arc of a circle cut- 
ting the path of the crank-pin in the three points e, f g. Join 
each of these points with the point D, thus determining the po- 
sition, I) e, of the crank at the instant of admission, its position, 
Df at the instant of cut-off, and its position, D g, at the instant 
of release. Bisect the angle e Dfhj a, straight line, D L ; make 
D Lot any convenient length, and upon it, as a diameter, describe 
a circle, and note the point, M, in which it cuts D e. From D as 
a centre, and with i) J/ as a radius, describe an arc of a circle, 
M R N. Measure the lengths of the lines D M and D L, and 
divide the former by the latter. Subtract the quotient from 1, and 
divide the width of steam-port by the difference. This gives the 
travel of the valve. Multiply the travel of the valve by half the 
quotient obtained above, and the product will be the steam-lap. 
The angle L 1) I is the angular advance of the eccentric. Di- 
vide the length of 8 Rhy the length of L D, and multiply half 
the quotient by the travel of the valve : the product is the steam- 
lead. 

Next produce the line L D, making I) equal to I) L, and 
upon Z) 0, as a diameter, describe a circle, noting the point, P, in 
which it cuts D g, the position of the crank at the instant of re- 
lease. Divide the length of Z) P by the length of D 0, and 
multiply half the quotient by the travel of the valve, which gives 
the exhaust-lap. With i) as a centre, and i> P as a radius, de- 
scribe an arc, P T Q, noting the points, T and Q, in which it cuts 
A By and the circle whose diameter is 1) 0. Divide the length of 
T TFby^the length of H 0, and multiply half the quotient by the 
travel of the valve : the product is the exhaust-lead. Through the 



82 ENGINEERING. 

point Q draw tlie line D h : this is the position of the crank at 
the instant the exhaust-valve closes and cushion commences. 
With h as a centre, and A S, the length of the connecting-rod, 
as a radius, describe an arc cutting the line A B in the point H ; 
then G His the portion of the return stroke completed when the 
exhaust-valve closes. 

On account of the angularity of the connecting-rod, the points 
of cut-off and exhaust closure will vary somewhat on the re- 
turn stroke. They can be equalized by a slight change in the an- 
gular advance and length of the eccentric rod. 

VI. Example. — Tlie following example will serve to illustrate 
the application of the preceding principles : 

A valve is to be designed for an engine having a cylinder 20 
inches in diameter, and a stroke of 2^ feet, making 80 revolutions a 
minute. The length of the connecting-rod is 6:^ feet. The valve 
is to admit steam when the piston has made 0.997 of the stroke, 
is to close the steam-port at two thirds of the stroke, and open 
the exhaust when f\j^ of the stroke has been completed. 

The area of the piston, in square inches, is 0.7854 times 400 
(the square of 20), or 314.16, and the piston-speed is 400 feet per 
minute ; hence the proper port area is 0.07 times 314.16, or about 
22 square inches. Assuming the length of the port to be equal 
to the diameter of the cylinder, 20 inches, its width will be j-Q of 22, 
or 1.1 inches. The width of the bridge must be equal to the thick- 
ness of the cylinder, or 1^ inches. In the figure, make ^ >S^ equal to 
2i times A G, and B A, 0.997 of A G, A F, ^ of A G, and A G, 
0.95 of A G. Constructing the positions of the crank corre- 
sponding to these points of stroke, and making the other con- 
structions as explained above, suppose that the data obtained 
from the figure by measurement are as follows : 

Angle RDM, 5° ; angle M D N. 108f ° ; angle RDF, 
151^° ; angle T I) Q, 137i° ; angle L D I, angular advance of 
eccentric, 40f ° ; D M, 0.65 of an inch ; D L and I) 0, each 1.5 inches; 
B P, 0.19 of an inch ; SR, 0.1 of an inch ; T >F, 0.375 of an inch ; 
G II, part of return stroke completed when exhaust closes, 0.85. 
Dividing B M (0.65) hy B L (1.5), the quotient is 0.43+ ; sub- 
tracting 0.43 from 1, the remainder is 0.57 ; dividing twice the 
width of steam-port, 2.2, by 0.57, the quotient, the travel of the 
valve, is 3.86 inches. Multiplying ^ of 0.43 by 3.86, the product, the 
steam-lap, is 0.83 of an inch. Dividing B P (0.19) by D (1.5), the 
quotient is 0.127 ; multiplying i of 0.127 by 3.86, the product, the 
exhaust-lap, is 0.25 of an inch. Dividincr 8 R (0.1) by 1.5, the quo- 
tient is 0.067 ; multiplying ^ of 0.067 by 3.86, the product, the 
steam-lead, is 0.13 of an inch. Dividing T TF (0.375) by 1.5, the 
quotient is 0.25 ; multiplying i of 0.25 by 3.86, the product, the 
exhaust-lead, is 0.48 of an inch. Adding the ha' f -travel of the 
valve (1.93) to the width of the steam-port, 1.1, the sum is 3.03 ; 
subtracting the width of the bridge (1.125), the remainder, the 
width of the exhaust-port, is 1.91 in. The sum of the steam-lap 
(0 83), the exhaust-lap (0.25), and the width of the steam-port (1.1), 
the length of the vaUe-face, is 2.18 inches. The sum of twice the 
length of face (4.36), twice the width of bridge (2.25), and the 
width of the exhaust-port (1.91), the length of the valm, is 8.52 inches. 
In this example no attempt has been made to secure great accu- 
racy, and, as the measurements were made from a small sketch. 



ENGINEERIN"G. 83 

tliere may be considerable errors. In practice, a scale reading to 
hundredths of an inch should be used, and the figure should be 
constructed of full size, if possible. This can generally be done 
by laying down the positions of the crank in a small sketch, and 
then transferring them to a large drawing ; or the positions may 
either be calculated or taken from a crank-table, if one is avail- 
able. By making the drawing full size, and having marks on the 
shaft as described above, a template can be constructed from the 
drawing, for transferring the position of the eccentric to the 
shaft. It may be remarked, that however carefully the valve is 
proportioned and the adjustment of the eccentric effected, the en- 
gineer who desires to be certain that the valve-motion of his en- 
gine is properly arranged, will make the final test and adjust- 
ments with the aid of the steam-engine indicator. B. 

Testing Small Engines. — The apparatus needed is quite sim- 
ple, and can be readily constructed by the young mechanic. The 
following embrace the principal points that are generally of in- 
terest in regard to engines and boilers : Diameter of cylinder, 
length of stroke, diameters of piston-rod, connecting-rod, crank- 
pin, valve-stem, fly-wheel, and shaft ; lengths of connecting-rod 
and crank-pin, weights of whole engine and of fly-wheel, size of 
ports, stroke of valve, point at which steam is cut ofE, number of 
revolutions per minute, clearance at each end of cylinder, pres- 
sure of steam in boiler, dimensions and weight of boiler, diame- 
ters of steam-pipe and safety-valve, number of pounds of water 
evaporated, fuel burned per hour, and power of the engine. 
Many of these data are obtained at once, by direct measurement 
or weight. The diameter of the cylinder should be measured 
when it is at the temperature at which it is ordinarily maintained 
while running. The point of cut-off can generally be ascertained 
by removing the cover of the valve-chest, and observing the point 
at which the steam- valve closes when the engine is moved by 
hand. This should be done when the parts are heated. The 
clearance at each end of the cylinder includes not only the space 
between the piston and cylinder-head at the end of the stroke, 
but also the volume of the ports. A simple and accurate manner 
of measuring the clearance is to fill the cylinder with water, 
when the piston is at one end of the stroke, and then measure the 
water carefully in a cylindrical or rectangular vessel. The dif- 
ference between the volume of the water and the volume of pis- 
ton displacement (area of piston multiplied by length of stroke) 
will be the clearance. In measuring the piston displacement at 
the front end of the cylinder, the volume of the piston-rod (area 
of section of rod multiplied by length of stroke) must, of course, 
be deducted. 

The number of revolutions of the engine per minute can be de- 
termined approximately by observation ; but errors are apt to re- 
sult, especially in the case of small engines moving at a high 
rate of speed. Small shaft-counters can be obtained at a very 
reasonable price, and measurements made with them are far 
more likely to be accurate. 

Many small boilers are not provided with steam-gauges, so that 
the pressure of the steam can not be observed directly ; but all 
such boilers have, or should have, safety-valves, and the pressure 
of the steam can be determined from them. Secure the valve- 



84 ENGINEERING. 



stem of the safety-valve to the lever with wire or string, and at- 
tach a loop to the lever, into which pass the hook of an accurate 
spring-balance, arranging the loop so that it is directly over the 
centre of the valve-stem. Then take hold of the upper part of 
the spring-balance, and lift the valve slightly, noting the reading 
of the balance. Measure the lower diameter of the safety-valve, 
and find its area ; divide the reading of the spring-balance by the 
area of the valve, and the result will be the pressure, in pounds 
per square inch, at which the steam will raise the safety-valve. 
Suppose, for instance, that the diameter of the safety-valve is 1 
inch ; its area will be about i^o^o^o^ of an inch. Now, if the ten- 
sion of the spring-balance in raising the valve is 120 lbs., the 
pressure at which the valve will rise is the quotient arising from 
dividing 120 by foWo> or 153 lbs. per square inch. It will be 
easy to make a table for any particular case, giving the pressure 
corresponding to each pound or fraction of a pound of tension in 
the balance ; and by calculating in advance the reading of the 
balance for any given pressure, the weight can be adjusted on 
the lever until that tension is obtained, and the valve can thus be 
graduated to lift at any required pressure. Having determined 
the pressure at which the safety-valve will rise when the boiler 
is cold, raise the valve by means of the balance, from time to 
time, when the engine is working, and observe the tension. 
Find the pressure corresponding to this tension, and subtract it 
from the pressure at which the valve will be raised by the steam. 
The difference is the pressure in the boiler at the time. For ex- 
ample, suppose that in the last case the tension of the balance, 
on raising the valve when the engine was working, was 50 lbs. 
The pressure corresponding to this will be 50 divided by i\nfoi)» or 
about 64 lbs., so that the pressure in the boiler at the time 
would be the difference between 153 and 64, or 89 lbs. per square 
inch. By preparing a table showing the pressure in the boiler 
due to each pound of tension in the spring balance, the pressure 
at any time can be read off as soon as the indication of the balance 
is observed. 

The amount of water evaporated per hour and the fuel burned 
can, of course, be readily determined by measurement, drawing 
the water from a tank of known dimensions, and observing its 
state at the commencement and close of a trial, being careful to 
leave the water in the boiler at the same height at which it was 
at the commencement, and maintaining this height as constant 
as possible during the experiment. In measuring the fuel con- 
sumed, it is best to draw out the fire at the commencement of the 
trial, rekindling it as soon as possible, and charging all the fuel 
used from that time, hauling and quenching the fire immediately 
at the close of the trial, and weighing back all fuel that is uncon- 
sumed. In the case of small boilers heated by lamps, a measure- 
ment of the oil used between the beginning and end of the trial 
will generally be sufficient ; and if gas is employed as fuel, it 
will be necessary to attach a meter to the pipe, to determine the 
quantity consumed in any given time. 

To ascertain the power of the engine, the most convenient me- 
thod is, generally, to attach a friction -brake, shown in the ac- 
companying engraving, to the band- wheel. Hollow out two 
pieces of wood, B and C, so that they will fit the circumference of 



ENGINEERING. 



85 



the band-wheel, A, and attach light plates of metal, D and E, to the 
sides, so that the pieces of wood can not slip off when secured in 
position. Provide two belts, F, G, countersinking the heads, H 




THE FKICTION-BRAKE. 

and I, into the upper piece of wood, so that they can not turn, 
and put nuts and washers, K and L, on the other ends, so that 
the two pieces of wood can be clamped on the band wheel as 
tightly as is necessary. Make the upper piece of wood somewhat 
longer than the other, and pass a rod, M, through the end. On 
this rod weights, N, are to be placed, and the lower end of the 
rod is hooked to the piston-rod of a small cylinder, O. The pis- 
ton, P, fits loosely in this cylinder, which is filled with oil or wa- 
ter ; and the piston has small holes in it, so that it can move up 
and down without much resistance, if moved slowly, but offers 
considerable resistance to sudden motion. The action of the ap- 
paratus will doubtless be apparent to our readers. By tightening 
the nuts on the bolts, F, G, there will be considerable friction be- 
tween the band-wheel and the pieces of wood. The rod M must 
then be loaded with suflScient weight, so that the engine can just 
move at its regular rate of speed, and keep the upper piece of 
wood in a horizontal position. The friction on the band-wheel 
will cause it to become heated, unless some arrangements are 
made for cooling, either by keeping a stream of water running 
upon it, or immersing the lower part in a trough in which the 
water is constantly changed. The small cylinder, O, and piston, 
P, serve to counteract the effect of sudden shocks, which would 
otherwise throw the arm of the piece B from a horizontal position. 
Now it will be plain that, as the baiid-wheel revolves (constantly 
maintaining the arm, with the weight attached, in a horizontal 
position), the effect is the same as if it were lifting this weight by 
means of a rope running over a windlass, and the distance 
through which it would lift the weight in a given time is the 
same as the weight would move if the whole apparatus were free 
to revolve. If, for example, the wheel makes 300 revolutions in a 
minute, the distance from the centre of the wheel to the centre of 
the weight is 1 foot, and the weight is 10 lbs. ; this weight, if 
free to revolve, would move in each revolution through the cir- 



86 ENGINEERING. 



cuniference of a circle whose radius is 1 foot, and in a minute 
would move 300 times as far, or about 1885 feet. The work of 
the engine in a minute, then, will be that required to lift 10 lbs. 
through a height of 1885 feet, or 18,850 foot lbs. ; and as one 
horse-power is the work represented by 33,000 foot lbs. per min- 
ute, the engine would be developing a little more than half a 
horse-power. 

In makincr experiments with the friction-brake, the apparatus 
should be placed loosely on the band- wheel ; and before the 
weights are attached, a spring-balance should be secured to the 
arm, at the centre of the hole for the rod M, and the reading not- 
ed when the arm is in a horizontal position. This reading must 
be added to the weights that are afterwards attached. The hori- 
zontal distance from the centre of the wheel to the centre of the 
rod M, should be carefully measured. Then start the engine, 
with the throttle-valve wide open, and screw up the nuts K L gra- 
dually, adding weights at N. It will then only be necessary, when 
sufficient weights are added, to keep the wheel cool, and occasion- 
ally adjust the nuts K L, should the brake bind or become too 
loose from any cause. Should it be difficult or inconvenient to 
maintain the arm in a horizontal position, note carefully the posi- 
tion it assumes during the test ; and for the radius to be used in 
the calculation, measure the distance a b from the centre of the 
wheel to the centre of the rod M, in a direction perpendicular to 
the direction of the rod. 

Instead of the weights, N, and cylinder, O, a spring-balance may 
be attached to the end of the rod M, and secured to some fixed 
support, its readings during the trial being used in place of the 
attached weights. In this case, also, the weight of the apparatus 
must be first determined, and added to the readings of the sprinof- 
balance. The plan represented in the engraving is, however, the 
best. 

The above are, in detail, the methods to be pursued in pre- 
paring a report of the performance of small engines and boilers. 
Although they are far from fulfilling all the requirements of 
a scientific test, they will give very accurate results if carefully 
conducted. B. 

Turbine Wheels, Effective power of. — It is important, in se- 
lecting a good wheel, to be assured that it will furnish ample 
power. After ascertaining a reliable maker, in order to determine 
the exact size of the wheel it is necessary that at least one third 
should be allowed for variations in water levels, and for the loss 
consequent to the wear of wheels and gates ; and, in addition, 
figures should be made, based on but a little more than a half 
gate of water to the wheel. The best wheels afford almost all of 
their power at a five-eighths gate or under, and a difference be- 
tween a half and full gate is not more than should be the margin 
necessary to regulate speed. In use it will be found that open- 
ing gates seven-eigliths or fully simply amounts to a large 
consumption of water, generally without producing five or ten per 
cent additional power. Some good wheels jjive less power when 
at full than at part gates. The rule should be to buy a wheel 
amply sufficient at not much above half gate, allowance bein^ 
made for over- estimate of power. We think the experience of all 
who have placed wheels with a less liberal allowance will bear 



ENGINEERING. 87 

out and confirm this rule. Allowing one fourth for the friction 
of the shaftmor of a cotton or woolen mill, without adding one 
third more for a reserve when in actual use, will scarcely fail to 
cause a manufacturer to wish that he had bought a larger wheel 
Actual tests, accurately conducted, of 31 styles of turbines show 
the comparative range of effective force, under the best possible 
advantages, to be as follows : At quarter gate, from IB to 50 per 
cent ; half gate, from 11 to 71 per cent ; three-quarter gate, from 
31 to 82 per cent, and at full gate, from 52 to 84 per cent, the best 
wheels giving out about all of their power at from five-eighths to 
three-quarters openings ; while the lower classes give but little 
power unless flooded with water, and even then fall far short of 
the amount claimed for them. Another reason why large wheels 
should be used is that, almost universally, high and low points of 
the head and tail waters so reduce the force of wheels as to cause 
partial stoppages of machinery, unless there is surplus power 
when the water is at the ordinary stage. 



THE STEAM-BOILER AND ITS ATTACHMENTS. 

Boiler, Cleaning the. — The flues or tubes of a boiler should 
be cleaned about once a week, with a brush or scraper. In case 
incrustation has formed in them, they can be cleaned by a jet of 
steam from a rubber hose. A boiler should be blown down 
and cleaned, under ordinary circumstances, about once a month. 
The fire should first be hauled ; and then, if possible, it is best to 
let the boiler stand until the water becomes tolerably cool, say for 
12 hours, after which the water may be allowed to run out. Then 
remove the man and handhole plates, enter the boiler, and clean 
it with scrapers and brushes in every part that can be reached. 
It should then be washed out with cold water from a hose, and 
this washing with a hose is the only means of cleaning those 
parts of a boiler that can not be reached by hand. There are 
many boilers into which a man can not enter, and of course these 
can only be washed out. When the fire is hauled, all leaks in 
the boiler should be repaired. Leaky parts exposed to the fire 
must have hard patches riveted on ; *in other places soft patches 
secured by bolts can be used, each patch having a lip around it, 
and the joint being made with a putty composed of red and white 
lead. Leaky rivets or seams can sometimes be made tight by 
calking. Small leaks around the ends of tubes can often be 
stopped in the same way, but as a general thing a leaky tube 
must either be replaced or plugged. To plug a tube, drive a 
white-pine plug tightly into each end, and cut it off even with 
the tube-heads ; then pass a bolt through the tube, with cup 
washers on each end, and screw it up tightly, putting putty under 
the washers. B. 

Boilers, Cylindrical. — TofindtJce necessary thickness in inches 
for the shell. — Multiply the pressure of steam in pounds per 
square inch by the diameter of the boiler in inches, and multiply 
this product by 0.0002 for a copper boiler with single-riveted 
shell ; by 0.0001563 for a copper boiler with double-riveted shell ; 



88 ENGINEERING. 

by 0.0001316 for a wrouglit-iron boiler with single-riveted shell ; 
by 0.0001111 for a wroiight-iron boiler with doable-riveted shell ; 
by 0.0001 for a steel boiler with single-riveted shell ; and by 
0.00008333 for a steel boiler with double-riveted shell. 

In illustration of the rule, suppose that it is required to find the 
necessary thickness for the shell of a copper boiler 60 inches in 
diameter, double riveted, for a pressure of 40 lbs. per square inch. 

First take the product of 40 and 60, which is 2400, and multiply 
this by 0.0001563, which gives 0.375, or | of an inch, as the neces- 
sary thickness. 

To find the safe pressure in pounds per square mc/i.— Divide the 
thickness of the plate in inches by the diameter of the boiler in 
ifiches, and multiply the quotient by 5000 for a copper boiler with 
single-riveted shells ; by 6400 for a copper boiler with double- 
riveted shell ; by 7600 for a wrought-iron boiler with single-rivet- 
ed shell ; by 9000 for a wrought-iron boiler with double-riveted 
shell ; by 10,000 for a steel boiler with single- riveted shell ; and 
by 12,000 for a steel boiler with double- riveted shell. 

Thus, to find the safe pressure for a boiler 32 inches in diame- 
ter, the shell being made of wrought-iron plates \ of an inch 
thick, single-riveted : First divide \ by 32, which gives tys, and 
multiply this by 7600, the product, 59| lbs. per square inch, being 
the pressure required. 

Thickness, in inches, of flat heads (not stayed).— K\jli\i^\y the 
square root of the pressure in lbs. per square inch by the radius 
of the shell in inches, and by 0.013333 for a head of copper ; by 
0.010541 for a head of wrought-iron ; and by 0.0081649 for a head 
of steel. 

A steel boiler has a diameter of 24 inches, and the pressure of 
the steam is 60 lbs. per square inch : The thickness of the head 
is the product of 7.746 (the square root of 60), 12, and 0.0081649, 
which is equal to 0.7766, or about |f of an inch. 

Safe pressure, in pounds per square inch, for flat heads {not 
stayed}. — Divide the square of the thickness of the plate in inch- 
es by the square of the radius of the shell in inches, and multi- 
ply the quotient by 5625 for a head of copper ; by 9000 for a 
head of wrought-iron ; and by 15,000 for a head of steel. 

Suppose the heads of a boiler are of steel, i inch in thickness, 
and that the diameter of the boiler is 24 inches : .25 (the square 
of I), divided by 144 (the square of the radius), is .00174, and the 
product of .00174 and 15,000, 26 lbs., is the pressure required. B. 

BoiLEKS, Heating surface ot—Note : In the following rules all 
dimensions are to be taken in feet. 

(a) Cylindrical boilers.—Tske the product of (1) the diameter of 
the boiler, (2) the length of the boiler, and (3) 1.5708. 

Suppose a given boiler has a diameter of 36 inches, and a 
length of 20 feet, its heating surface is the product of 3, 20, and 
1.5708, or about 94J- square feet, 

(6) Cylindrical flue boilers. — Take the product of the diameter 
of the boiler, the length, and 1.5708, and add it to the product of 
(1) interior diameter of flue, (2) length of flue, (3) number of flues, 
and (4) 3.1416. 

Suppose that a flue boiler is 4 feet in diameter, 22 feet long, and 
has two flues, each with an interior diameter of 15 inches. Then 
the heating surface is equal to the product of 4, 22, and 1.5708, or 



ENGINEERING. 



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90 



ENGINEERING. 



nearly 138i, increased by the product of 1.25, 22, 2, and 3.1416, 
or about 172f , making the total heating surface 311 square feet. 

(c) Cylindrical tubular boilers. — Find the product of the diame- 
ter of the boiler, the length, and 1.5708, and add this to the pro- 
duct of the length of the boiler, the number of tubes, and the 
heating surface of a tube per foot of length. 

The preceding table gives the heating surface per foot of 
length for the standard sizes of tubes. 




LOCOMOTIVE BOILER. 

Example. — A cylindrical tubular boiler has a diameter of 42 
inches, is 16 feet long, and contains 40 tubes, each 4 inches out 
side diameter. 

The product of 3i, 16, and 1.5708 is nearly 88. 

The product of 16, 40, and 0.977 (the internal surface of the 
tube, per running foot) is about 615, so that the whole heating 
surface is 703 square feet. 

{d) Locomotive boilers. — I. Add together the following quanti- 
ties : (1) The product of the length of the line bounding the 
cross-section of the furnace, and the length of the furnace. (2) 
Twice the area of the cross-section of the furnace. (3) The pro- 
duct of the length of the tubes, the number of tubes, and the 
heating surface of a tube per foot of length. 

II. Subtract from this sum the sum of the following quanti- 
ties : (4) The area of the furnace-door. (5) The product of the 
number of tubes, the square of the internal diameter of a tube, 
and 0.7854. 



ENGINEERINGr 



91 



As an example of tlie use of this rule, suppose it is required to 
determine the heating surface of a boiler having the dimensions 
noted in the engravings, Fig. 1 being a cross-section of the 




LOCOMOTIVE BOILEK. 

boiler at the furnace, showing also the furnace door in dotted 
outline, and Fig. 2 a longitudinal section. (1) The length of the 
line bounding the cross-section of the furnace is the sum of twice 
3.5, 1.5708, and 2.5, or 11.07, and the product of 11.07 and 4 is 
44.28. (2) The area of the cross -section of the furnace is the sum 
of 3.5 squared, 2| times ^, and 0.7854 divided by 2, or about 
13.89. Twice 13.89 is 27.78. (3) The product of 8, 20, and 0.977 is 
157.32. The sum of 44.28, 27.78, and 157.32 is 229.38. (4) The 
area of the furnace-door is the snm of 1.5 times 1.25, and 0.3927 
times 1.5 squared, or about 2.76. (5) The product of 20, 0.311 
squared, and 0.7854, is about 1.52. 

The sum of 2.76 and 1.52 is 4.28. The difference between 229.38 
and 4.28 is about 225* square feet, the heating surface required. 

(e) Vertical boilers. — I. Take the sum of the following quanti- 
ties : (1) The product of the diameter of furnace, height of same, 
and 3 1416. (2) The product of the diameter of the furnace 
squared and 0.7854. (3) The product of the number of tubes, 
length of same, and heating surface per foot of length. 

11. Subtract from this sum the product of the number of tubes, 
the internal diameter of a tube squared, and 0.7854. 

Example. — Required, the heating surface of a vertical boiler 
with the following dimensions : Diameter of furnace, 24 inches ; 
height of furnace, 18 inches ; 40 tubes, each 2 inches outside di- 



92 



ENGINEERING. 



ameter, 6 feet long. (1) The product of 2, 1.5, and 3.1416 is 
9.42. (2) The product of 4 and 0.7854 is 3.14. (3) The product of 
40, 6, and 0.4739 is 113.74. The sum of 9.42, 3.14, and 113.74 is 
126.3. The product of 40,0.02274 (the square of 0.1508), and 
0.7854 is about 0.72. The heating surface is the difference be- 
tween 126.3 and 0.72, which is about 125.6 square feet. B. 

Boilers, Horizontal, Setting. — The best way is to have the 
fire-box at least as wide as the boiler, and have as much heating 
surface as possible ; but below the water-line all passages should 
be made large, so as to allow a free passage to the heated gases, 
and where they leave the boiler, a damper should be provided. 
The bridge-wall should be high enough to prevent coal from 
being thrown over, and the grates low enough to allow ample 
room for combustion. Nothing can be gained by putting the fire 
near the boiler or contracting any of the passages ; it is better to 
let the heat diffuse itself fully throughout the entire heating 
surface. ^ 

Boilers, Priming in. — If your boiler primes, either " swap" it 
off for another or superheat your steam moderately ; but beware 
of anti-priming doctors and their remedies. 

Boilers, Rules for firing under. — (1) Begin to charge the fur- 
nace at the bridge end, and keep firing to within a few inches of 
the dead-plate. (2) Never allow the fire to be so low before a 
fresh charge is thrown in, so that there shall be at least 4 or 5 
inches of clear, incandescent fuel on the bars, equally spread over 
the whole. (3) Keep the bars constantly and equally covered, 
particularly at the sides and bridge end, where the fuel burns 
away most rapidly. (4) If the fuel burns unequally or in holes, 
it must be leveled and the vacant spaces filled. (5) The large 
coals must be broken in pieces not larger than a man's fist. (6) 
Where the ash-pit is shallow, it must frequently be cleaned out ; 
a body of hot cinders will overheat and burn the bars. 




STRAIGHTENINa TALL CHmNETS. 



Chimneys, To straighten tall.— Have a number of oak wedges 
made of suflSicient length to pass through the entire thickness of 



ENGINEERING. 93 



the cliimney and project sufficiently on the outside. Place them 
in sets of three each, one over the other, as shown in the en- 
gravings having the surfaces in contact straight and smooth, 
and black-leaded to diminish friction. Commence on the oppo- 
site side to that in which the chimney leans ; cut through to the 
inside, insert one set of wedges, and wedge above and under them 
until they take a bearing. Kepeat the process around the chim- 
ney, except on the lowest side, leaving spaces of a foot or more 
between each set of wedges. Then, by driving the centre wedge 
in each set inwards, as much of the chimney as rests on them is 
gradually lowered just at the places and to the amount required 
to bring it to an exact perpendicular. When that is done, brick 
up the intervening spaces, loosen and withdraw the wedges, and 
brick up in their places. This requires careful and skilful work. 

Chimneys, Proportioning. — The general rule is to make the 
cross-section of the chimney, which may be either round or square, 
from -^ to Yo of the grate-surface, and the height from 50 to 70 
feet. 

2^0 determine the amount of coal which will he burned per square 
foot of grate per hour, with good proportions, by Professor Thurs- 
ton's rule. — Subtract one from twice the square root of the height. 
Example : What will be the amount of coal burned per square 
foot of grate surface per hour, the chimney being 49 feet high, 
and suitably proportioned? The square root of 49 is 7 ; twice 7 
is 14 ; 14 less 1 is 13, which is the amount of coal required in 
pounds. 

To determine the height required to give a certain rate of com- 
hustion. — Add 1 to the weight to be burned per square foot per 
hour ; divide by 2 and square the quotient. Example, same as 
above, worked backwards, thus : What height of chimney is re- 
quired to burn 13 pounds of coal per square foot of grate sur- 
face per hour ? 13 and 1 are 14 ; 14 divided by 2 is 7 ; the 
square of 7 is 49, which is the height of the chimney in feet. 

Coal, Effect of damp air on. — It has been found by recent 
experiments on this subject, that the loss in weight, due to a 
slow oxidation and to the disengagement of gases which form the 
richest part of bituminous coal, may equal one third of the ori- 
ginal weight. The heating power in such coal was lowered to 47 
per cent of its former capacity. The same coal exposed to the air, 
but in a closed receptacle, did not lose more than 25 per cent of 
gas and 10 per cent of heating power. Bituminous coals alter 
most rapidly. This shows the disadvantage of damp cellars, and 
of leaving coal uncovered for long periods and subject to bad 
weather. 

Combustion and Fuel. — The principal constituents of coal are 
carbon, hydrogen, water, a little sulphur, ashes and clinker, the 
latter two substances consisting generally of silica, alumina, iron, 
lime, magnesia, and oxide of manganese. The principal combus- 
tible constituent of anthracite is fixed, uncom.bined carbon. The 
free-burning or semi-bituminous coals contain a considerable 
amount of hydrocarbon or volatile combustible matter, and bitu- 
minous caking coals have a larger percentage of volatile combus- 
tible. 

If a mass of coal is brought to a sufficiently high temperature 



94 ENGINEERING. 



(probably something above 1000° Falir.), the combustible mate- 
rials enter into chemical combination, and as much heat is given 
out as would be required to decompose the resulting products into 
their elements. When coal is burned the water is first expelled ; 
then the sulphur, if any is contained, is consumed, forming sul- 
phurous oxide ; after this the hydrogen in the volatile combusti- 
ble matter unites with oxygen, forming water ; and the carbon 
set free unites with oxygen, forming carbonic dioxide, if the tem- 
perature is sufficiently high and enough oxygen is present, or, 
under less favorable circumstances, either forming carbonic oxide 
or passing off unconsumed, as soot. The combustion of the fixed 
carbon next begins, the product of the combustion being carbonic 
dioxide or carbonic oxide, so that finally nothing is left except 
the ashes and clinker. 

It may be well to trace the effect of these various combina- 
tions : The water contained in the coal is expelled in the form of 
steam, so that it carries off some heat, and is a positive disadvan- 
tage. The complete combustion of a pound of sulphur produces 
about 4000 units of heat, but the amount of sulphur in coal is 
usually so slight that its heating qualities scarcely deserve to be 
regarded. The action of the sulphur on the material of the boiler 
is, however, a very serious matter. It has not yet been determin- 
ed by experiment what per cent of sulphur is sufficient to render 
a coal unfit for use in a furnace, but it is well known that many 
of the Western coals produce very bad effects when employed in 
locomotive boilers. A pound of hydrogen, combining with oxy- 
gen, forming 9 pounds of water, has a heating power of 62,082 
units. It seems doubtful, however, whether this amount of heat 
is available from the combustion of hydrogen in a boiler. The 
experiments by which this value was determined were made upon 
hydrogen in the gaseous state, and the steam resulting from the 
combustion was condensed. Now the hydrogen in coal is ordi- 
narily combined with carbon, and frequently with nitrogen, so 
that it must be separated from the combination before it can be 
united with oxygen, and heat is required for this separation. 
Again, in a boiler the products of combustion usually pass into 
the chimney at such a high temperature that the water, which is 
the result of the combustion of the hydrogen, passes off in the 
form of steam, and thus carries off a considerable quantity of 
what is commonly known as latent heat. This subject is one 
which has been but little considered by experimenters, and is 
worthy of more extended investigation. The volatile combusti- 
ble matter of coal generally contains oxygen in combination, and 
this must be changed into the gaseous state before being united 
with the hydrogen, an operation that requires as much heat as 
results from the new combination. Hence it is certain that the 
amount of hydrogen contained in coal must be diminished by one 
eighth of the weight of the oxygen before attempting to form any 
estimate of its heating qualities. 

The carbon of the ooal, as has been already stated, will unite 
with oxygen, forming carbonic dioxide, and may afterwards take 
up more carbon, and be converted into carbonic oxide. Now the 
result of the complete combustion of a pound of carbr)n is 3f lbs. 
of carbonic dioxide, and the combustion produces 14,500 units of 
heat. But a pound of carbon imperfectly burned produces 2i 



ENGINEERING. 



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96 ENGINEERING. 

pounds of carbonic oxide, and only 4400 units of lieat. In a fur- 
nace where the combustion is imperfect, the action is usually as 
follows : A pound of carbon is at first completely burned, forming 
3| pounds of carbonic dioxide, and then takes up another pound 
of carbon, producing 4|- pounds of carbonic oxide and 8800 units 
of heat. This carbonic oxide, however, if supplied with a suffi- 
cient amount of air, will burn and again form carbonic dioxide, 
so that the full effect of the combustion of the carbon will be 
realized. A practical application of this principle is seen in the 
combustion-chambers in boilers, which are designed to complete 
the combustion of the gases after they leave the furnace. 

Having disposed of the materials of the coal which escape into 
the chimney of a boiler, the ashes and clinker that remain should 
be cornsidered. The effect of these substances is injurious in se- 
veral ways ; they choke up the furnace, preventing free access of 
the air to the combustible materials, and instead of entering into 
combinations and producing heat, they require to be heated to the 
temperature of the furnace, and are then removed, without hav- 
ing produced an equivalent for the heat expended upon them. 

In ordinary boiler-furnaces, the amount of air required for the 
combustion of 1 pound of coal is about 24 pounds, or between 
280 and 800 cubic feet. 

For a table of the qualities of American coal from various loca- 
lities, compiled from Prof. Johnson's Report, see page 95. B. 

Feed- Water Heaters, Gain from the use of. — A unit of heat 
is the amount of heat required to raise the temperature of a pound 
of water one degree, the water being at the temperature of maxi- 
mum density, about 39.1° Fahrenheit. The table below shows 
the number of units of heat required to convert one pound of wa- 
ter, at the temperature of 32°, into steam of various pressures. 

Pressure of steam Pressure of steam 

in lbs. per sq. in., Units of heat, in lbs. per sq. in., Units of heat. 



by gauge. 




by gauge. 




1 


1148 


10 


1155 


20 


1161 


30 


1165 


40. 


1169 


50 


1173 


60 


1176 


70 


1178 


80 


..,. 1181 


90 


1183 


100 


1185 


110 


1187 


120 


1189 


130 


1190 


140 


1192 


150 


1193 


160 


1195 


170 


1196 


180 


1198 


190 


1199 


200 


1200 







In a non-condensing engine, if the exhaust steam escapes di- 
rectly into the atmosphere, it carries off most of the heat that was 
previously imparted to it by the coal in the furnace. This may 
be illustrated by an example. 

Suppose the steam is admitted into the cylinder of an engine at 
a pressure of 90 pounds per square inch, and exhausted at a pres- 
sure of 1 pound above the atmosphere, and that the temperature 
of the feed-water is 70°. If the feed-water had been at 32°, it will 
be seen that each pound of water would have required 1183 units 
of heat to convert it into steam of 90 pounds pressure ; but since 



ENGINEERING. 97 



the temperature of the feed was 38° above 32°, 38 units less, or 
1145, will be necessary. The exhaust steam carries away 1148 
less 38, or 1110 units of the heat that has been imparted to the 
steam by the coal, so that about 96.94 per cent of the heat is 
thrown away. Now, it costs money to heat this water, and the 
steam-user who pays $6.50 a ton for coal, which converts 15,000 
pounds of water into steam, might make up an account some- 
what after this manner: ''After evaporating 15,000 pounds of 
water at a cost of $0.00043+ per pound, I allowed 14,541 pounds 
to escape into the air without rendering me any equivalent, and 
only utilized 459 pounds in my engine ; so that really I pay at 
the rate of $0,014+ for every pound of water used." 

There are many steam-users to-day who could readily make up 
an account somewhat like the preceding. 

Now suppose that the steam- user, being convinced of the folly 
of paying for coal to raise steam which is blown away without 
doing any good, attaches a heater to his exhaust-pipe, and so 
raises the temperature of the feed-water to 200°, instead of 70°, 
as before. If this is done, and the heater is a good one, which 
does not increase the back pressure, each pound of water requires 
130 units less for its evaporation, and each pound of exhaust- 
steam carries away 130 units less than before ; and the steam«user 
can make up his account anew, as below : 

'' One ton of coal now evaporates about 16,900 pounds of water, 
at a cost of $0.00038 per jTound, and 600 pounds of this water are 
utilized in the engine ; so that I now pay $0.0108 for each pound 
of water that produces useful effect." 

If he had an engine of 100 horse-power, using 30,000 pounds of 
steam a day, and working 300 days in a year, he would find that 
the difference in his coal bill, before and after the change, would 
be the difference between $3870 and $3420, or $450. B. 

Fire-Clay for boiler-furnaces. — Take common earth, well 
mixed with water, to which is added a small quantity of rock- 
salt ; let the water stand until the salt dissolves, which will take 
about 2 or 3 hours. It is then ready for use. Apply it as fire- 
clay is used, and your furnace will stand much longer. 

Flue-Sheets, To calk leaks in. — Use a reflector (a tin plate 
will do) adjusted in front of the furnace-door, so as to throw 
light on to the flue-sheets, while calking leaks. 

Flues, Wrought- Iron. — Thickness in inches of a wrought-iron 
flue exposed to external pressure : I. Find (1) the product of the 
diameter of the flue in inches, (2) the length of the flue in feet, (3) 
the pressure of steam in lbs. per square inch, and (4) .000,009,091. 

II. Extract the square-root of this product. 

Suppose, for example, that a flue is 12 inches in diameter and 6 
feet long, and that the pressure of steam is 40 lbs. per square inch : 
The product of 12, 6, 40, and 0.000,009,091 is about 0.02618, and 
the square-root of this number is 0.1618+, or about 3% of an inch. 
It will be observed that the thickness of a flue increases directly 
as the length. Thus, other things being equal, a flue that is 12 
feet long must be twice as thick as one that has a length of 6 
feet. In making long flues, it is common to strengthen them at 
intervals by bands, thus converting them into a series of short 
flues, so far as the strength is concerned. 



98 ENGINEERING. 



Safe pressure in lbs. per square inch for a lorought-iron flue 
exposed to external pressure : Multiply the square of the thickness 
in inches by 110,000, and divide this product by the product of 
(1) the diameter of the flue in inches, and (2) the length of the 
flue in feet. 

Example. — What is the safe pressure for a flue 15 inches in 
diameter, 8 feet long, and f of an inch thick ? 

The product of 0.140,625 (the square of the thickness) and 110,- 
000 is 15,468.75. Dividing this by 15 times 8, or 120, the quotient 
is about 128.9 lbs., the pressure required. B. 

Gauges, mercurial steam. Keeping clean. — This can be done by 
putting a little glycerine or sulphuric acid on the surface of the 
mercury. This serves as a lubricator of both glass and metals, 
and prevents their adhesion. 

GrAUGES, Water and steam. — When a boiler is in use, the 
gauge-cocks should frequently be tried to see that they are not 
choked up, and the glass gauge should often be blown out. After 
ascertaining the proper place for the weight on the lever of the 
safety-valve, a stick should be secured to the lever with wire, so 
that the ball can not be moved out any further. A cord should be 
secured to the safety-valve lever, within easy reach of the engi- 
neer, so that the valve can be opened by hand if it sticks, and 
the safety-valve should be tried at least once every day, to ascer- 
tain whether or not it is in working ordgr. 

A steam-gauge should be tested at least once a year, and the 
engineer should frequently try its accuracy by allowing the 
steam to raise the safety-valve, and noting the pressure shown 
by the gauge. The hand of a steam-gauge sometimes sticks, and 
the engineer should tap the face of the gauge lightly several times 
a day, to assure himself that it is in working order. He may 
also shut off the steam from the gauge-pipe, and open the drip- 
cock, noting whether the hand goes back promptly to 0, and re- 
turns to the former reading when steam is again turned on. 

In testing a boiler, warm water should be used, and a better 
test, when this is possible, is to enter the boiler and make a 
thorough internal examination. 

In leaving a boiler for the night, the fire may either be hauled 
or banked. If it is to be banked, it should first be cleaned and 
then pushed back and covered with coal, the boiler being left 
with the furnace-door open and the damper closed. B. 

Joints, Riveted, Proportions of. — (a) Diameter of rivet in 
inches : Multiply the thickness of plate in inches by 2 for plates 
up to f of an inch thick, by 1.5 for plates from f to f of an inch 
thick, by 1.25 for plates from f to f of an inch thick, and by 
1.125 for plates from f to 1 inch thick. 

{h) Length of rivet under the head, in inches : Multiply the 
thickness of the plate in inches by 4.5. 

(c) Distance between rivets, from centre to centre, in inches : (1) 
Single-riveted joints : Multiply the thickness of plate in inches by 
6 for plates up to ^ of an inch thick, by 5 for plates from ^ to f 
of an inch thick, by 4 for plates from | to f of an inch thick, and 
by 3 for plates from f to 1 inch thick. 

(2) Each line of rivets, double-riveted joiiits : Multiply the thick- 
ness of the plate in inches by 7 for plates up to J of an inch thick, 



ENGINEERING. 



99 



by 6 for plates from J to i^ of an inch thick, by 5 for plates from 
-i\ to -le of an inch thick, and by 4 for plates from t^ to 1 inch 
thick. 

(d) Lap to be given to joint, in inches: (1) Single-riveted joints : 
Multiply the thickness of plates in inches by 6 for plates up to | 
of an inch thick, by 4.5 for plates from f to f of an inch thick, 
and by 4 for plates from f to 1 inch thick. 

(2) Double-riveted joints : Multiply the thickness of plate in in- 
ches by 10 for joints up to f of an inch thick, by 7.5 for joints 
from I to f of an inch thick, and by 6.7 for joints from f to 1 
inch thick. 

A table is appended, giving the thickness of plate in decimals 
of an inch, varying by sixteenths : 



Halves. 


Fourths. 


Eighths. 


Sixteenths. 


Decimals. 






1 


1 

2 


1 


0.0625 

0.125 

0.1875 

0.25 

0.3125 

0.375 

0.4375 

0.5 

0.5625 

0.625 

0.6875 

0.75 

0.8125 

0.875 

0.9375 

1. 






2 






3 






4 

5 






2 


3 






6 






4 


7 




1 


8 






3 

4 


5 


9 






10 






6., 

7 ... 

8 


11 






12 

13 






14 

15 




2 


16 













The following example will serve to illustrate the rules : 
What should be the proportions of a single-riveted joint for a 
boiler made of plates \ of an inch thick ? 

Diameter of rivets is twice 0.125, or J of an inch. Length of 
rivets under head is 4.5 times 0.125, or -^^ of an inch. Distance 
between centres of rivets is 6 times 0.125, or f of an inch. Lap 
of joint is 6 times 0.125, or f of an inch. B. 

Lead, Effect of steam on. — Lead in contact with steam under 
pressure of over 10 lbs. per square inch very soon loses its 
strength, and it is therefore good neither for packing joints nor 
for conveying steam. 

Pipes, Steam, Burst. — Steam-pipes which have cracks in them 
from having burst, may be repaired by heating and then soldering 
them. 

Pipes, Steam, Condensation in subterranean. — To prevent this, 
inclose the pipe in another larger pipe, and fill the space between 
the two with plaster-of-Paris or charcoal. The outside pipe 
should be water-tight. 

Pipes, Steam, Isolating material for. — Take 132 lbs. limestone, 
385 lbs. coal, 275 lbs. clay, and 330 lbs. sifted coal-ashes. This 
is finely pulverized, and mixed with 660 lbs. water, 11 lbs. sul- 



100 EIS'GINEERING. 

pliuric acid at 50° B., and about 160 lbs. calves' hair or hog- 
bristles. The compound is applied to the pipes in coats of 0.4 
inch thickness, repeated until a thickness of an inch and a half 
is obtained, when a light covering of oil is given. 

Pipes, Steam, To prevent cracking, from freezing. — Steam-pipes 
apt to fill with condensed water and burst from freezing should 
have small holes with plugs to them, the plugs to be taken out 
at night. 

Sawdust as Fuel, To burn. — A saw-mill owner solves the 
problem of usint^ saw-dust as fuel as follows. His boiler was a 
return tubular, 14 feet 6 inches long and 54 inches in diameter, 
with 64 three-inch tubes, and brick firebox 48 x 56 x 27 inches 
high ; bridge- wall was 7 inches at centre, rounded to the sides 
of boiler. He states : ''1 lowered the bridge- wall 13 inches 
(keeping the same circle as before), lowered the paving in rear 
of firebox to a level with the grate-bars, and obtained a barrel of 
furnace-slag from 3 to 7 or 8 inches in size and 1 or 1| inches 
thick, which I placed on the grate-bars, about half covering 
them. I fired with wood ; and when the slag got heated, I 
threw in the sawdust, which burned very well but smoked fear- 
fully (clouds would arise from the smoke-stack). I then intro- 
duced a 2inch pipe, with about fifty :^-inch holes, directly behind 
the bridge- wall, leaving both ends of pipe open ; after which, I 
never had a particle of trouble either in keeping up steam or in 
burning up the smoke. Not even in firing up did I ever see any 
smoke come out of the stack, which was 30 feet high and 32 
inches square, enlarged near top and to the top to 36 inches in- 
side measurement. I forgot to state that I covered the top of 
boiler with sheet-iron, then laid brick on it, covering the inter- 
stices with sand. The sheet-iron was to prevent the sand from 
wedgintr off the wall when the boiler expanded.'' A system of 
alternate firing, and with grates so arranged as to peimit some 
charred fuel to fall through and burn in the ash-pit, gives the 
best results. 

Scale in Steam-Boilers, Prevention of. — (1) Use as pure 
water as your locality affords. (2) Clean and scrape your boiler 
as often as you possibly can. (3) Blow off without excess. (4) 
In case of salt or brackish waters, never use steam of over 90 
lbs. pressure to the sq. in. (5) In case of sulphate of lime waters, 
never use steam of over 70 lbs. pressure. (6) In case of water 
iholding carbonate of lime in solution, pass it through a feed- 
water heater made hot by exhaust steam or waste heat. (7) In 
case of muddy waters use large feed-water cisterns or reservoirs, 
on the bottom of which the suspended earthy matters will * soon 
form a soft deposit, when the surface water can be drawn off for 
use. When using hard water, save the drippings of the exhaust- 
pipe, and the condensation of the safety-valve blow-off, and 
from the cylinder, and use the water thus obtained to fill the 
boiler after blowing off. The result will be surprising in its ef- 
fect in loosening scale. 

Slack, To burn as fuel. — A correspondent, who has practical- 
ly investigated this subject extensively, says : Slack requires 
the grate-bars to be very open. I have used bars with open- 



EJ^GINEERIISTG. 



101 



ings of 1| inclies. Tlie only secret in using slack with any 
kind of a furnace is to have the grate-bars open enough so that 
the fire can be kept open from the under side of the grates with 
the poker. Some coal, of course, will go through at first ; but 
coarse coal and wood can be used to start with, and what falls 
through the grate must be raked out and put in again. The coal 
will soon cake so that it will not waste. Make the furnace wider 
than usual, in building it, with doors in the side of the front, 
similar to furnaces for burning sawdust. For some varieties of 
coal, it will be found beneficial to wet the coal before throwing 
it into the furnace ; this helps to run the coal together. Then 
put in the coal at the side doors, and let it alone till it cakes ; 
then with the poker roll it into the centre of the fire. It will be 
in large lumps and will not waste, and there will always be a 
good fire in the centre. Never smother it with fresh coal. A 
system of introducing comminuted fuel with the air required for 
its combustion, by means of a fan-blower, has been introduced 
by a Boston firm. 

Specific Heat. — Table showing the number of units of heat re- 
quired to raise the temperature of one pound of a substance one de- 
gree Fahrenheit. 



Air 0.23740 

Alcohol (liquid) 0.61500 

(vapor) 0.45340 

Aluminum 0.21430 

Ammonia (vapor) 0.50830 

Anthracite coal 0.20100 

Antimony 0.0507? 

Aragonite. 0.20850 

Arsenic 0.08140 

Benzine 0.45000 

Bismuth (solid) 0.03084 

(liquid) 0.03630 

Bituminous coal 0.20085 

Boron 0.25000 

Brass 0.09391 

Bromine (liquid) 0.10700 

'' (gas) 0.05550 

Cadmium 0.05669 

Carbonic acid 0.21630 

'' oxide 0.24500 

Chalk 0.21485 

Charcoal 0.24150 

Chloride of barium 0.89570 

'' calcium.... 0.16420 

'^lead 0.06641 

'' magnesium. 0.19460 

" ''manganese. 0.14250 

Chloride of strontium. . 0.11990 

''zinc 013618 

Chlorine (gas) 0.12100 

Chromium , 0.12000 

Cobalt 0.10730 



Copper. 0.09515 

Corrosive sublimate. . . . 0.06889 

Corundum 0.19762 

Diamond 0.14687 

Ether (liquid) 0.50342 

" (vapor) 0.48100 

Fusel Oil 0.56400 

Galena 0.05086 

Glass 0.19768 

Glucinum. 0.23080 

Gold 0.03244 

Graphite 0.20083 

Hydrochloric acid 0.18450 

Hydrogen 3.40900 

Ice 0.47400 

Iceland spar 0.20858 

Indium 0.05700 

Iodide of mercury 0.04197 

" potassium 0.08191 

" silver 0.06159 

Iodine (solid) 0.05412 

" (liquid) 010822 

Iridium 0.03259 

Iron 0.11380 

Iron pyrites 0.13001 

Lead (solid) 0.03065 

" (liquid) 0.04020 

Lithium 0.94080 

Magnesium 0.24990 

Manganese 0.12170 

Marble 0.20989 

Mercury (liquid) 0.03332 



102 



ENGINEERING. 



Mercury (solid) 0.03192 

Molybdenum 0.07218 

Nickel 0.11080 

Niobium 0.06820 

Nitrate of sodium 0.27821 

" silver 0.14352 

Nitre 0.23875 

Nitric oxide 0.23150 

Nitrogen 0.24380 

Nitrous oxide 0.22380 

Oil of turpentine (liq'd) 0.46727 
'' '' '' (vapor). 0.50610 

Olefiant gas 0.40400 

Olive oil 0.31000 

Osmium 0.03113 

Oxygen 0.21750 

Palladium 0.05928 

Petroleum 0.46840 

Phosphorus 0.18870 

Platinum.. 0.03243 

Potassium 0.16956 

Rhodium 0.05803 

Kuthenium 0.06110 

Salt 0.17295 

Sapphire 0.21737 



Selenium 0.07446 

Silica 0.19132 

Silicon 0.17740 

Silver 0.05701 

Sodium 0.29340 

Steam 0.48050 

Steel 0.11750 

Sulphide of carbon 0.15700 

" zinc 0.12813 

Sulphur (native) 0.17760 

(purified) 0.20259 

(liquid) 0.23400 

Sulphuric acid 0.34300 

Tantalum 0.04840 

Tellurium 0.04737 

Thallium 0.03355 

Thorinum 0.05800 

Tin (solid) 0.05623 

'' (liquid) 0.06370 

Tungsten 0.03342 

Uranium 0.06190 

Vanadium 0.08140 

Water 1.00000 

Wood spirit 0.64500 

Zinc 0.09555 

B. 



Stayed Surface, Safe pressure, in lbs. per square inch, for 
a. — Divide the square of the thickness of the plate in inches, by 
the square of the distance between stays, in inches, and multiply 
the quotient by 16,875 for a copper plate, by 27,000 for a 
wrought-iron plate, and by 45,000 for a steel plate 

Example. — What is the safe pressure for a plate of wrought 
iron, J of an inch thick, secured by stays 6 inches from centre to 
centre ? 

The quotient arising from dividing 0.0625 (the square of ^) by 
36, is 0.00174. Multiplying 0.00174 by 27,000, the product is the 
required pressure, about 47 lbs. per square inch. B. 

Stayed Surface, Thickness of, in inches. — Multiply the 
square root of the pressure, in lbs. per square inch, by the dis- 
tance between centres of stays in inches, and multiply this pro- 
duct by 0.007698 for a copper plate, by 0.0060858 for a wrought- 
iron plate, by 0.0047141 for a steel plate. 

For a copper fire box, in which the stays are 10 inches apart 
from centre to centre, and the pressure of steam is 60 lbs. : The 
thickness of plate is the product of 7.746 (the square root of 60), 
10, and 0.007698 ; which is equal to 0.596, or about if of an 
inch. B. 

Stay, Proper diameter for a, in inches.— Multiply the distance 
between stays, in inches, by the square root of the pressure, in 
pounds per square inch, and multiply this product by 0.0206 for 
a copper stay, by 0.01784 for a wrought-iron stay. 

Example. — What is the proper diameter for wrought-iron 



EJS^GIN^EERING. 103 

stays, 6 inches between centres, the pressure of steam being 75 
pounds per square inch ? 

This is the product of 6, 8.66 (the square root of 75), and 
0.01784 ; which is equal to 0.92697, or about if of an inch. B. 

Stays, Distance between, in inches. — Divide the thickness of 
the plate, in inches, by the square root of the pressure, in lbs. 
per square inch, and multiply the quotient by 180, if the stayed 
surface is copper ; by 164, if the stayed surface is wrought iron ; 
by 212, if the stayed surface is steel. 

Suppose the fire-box of a boiler is to be made of steel plates, f 
of an inch thick, and the pressure of steam is to be 100 lbs. per 
square inch. 

Divide 0.375 by 10, and multiply the quotient, 0.0375, by 212 ; 
which gives 7.95, say 8 inches, as the proper distance between 
stays. B. 

I^ote. — The rules for stayed surfaces and flat boiler-heads are 
adapted from methods explained by Dr. Grashof in " Die Festig- 
keitslehre," Berlin, 1866. 

Valve, Safety, A simple test for determining the accuracy 
of. — Secure the valve-stem of the safety-valve to the lever with 
wire or string, and attach a loop to the lever, into which pass 
the hook of an accurate spring-balance, arranging the loop so 
that it is directly over the centre of the valve -stem. Then take 
hold of the upper part of the spring- balance, and lift the valve 
slightly, noting the reading of the balance. Measure the lower 
diameter of the safety-valve, and find its area ; divide the read- 
ing of the spring-balance by the area of the valve, and the result 
will be the pressure, in pounds per square inch, at which the 
steam will raise the safety-valve. Suppose, for instance, that 
the diameter of the safety-valve is 1 inch ; its area will be about 
I'm^ of an inch. Now, if the tension of the spring-balance in 
raising the valve is 120 lbs. , the pressure at which the valve will 
rise is the quotient arising from dividing 120 by I'^cft^, or 153 lbs. 
per square inch. 

A table is appended, giving the areas of valves for the ma- 
jority of cases that occur in practice : 

Table of Areas of Valves of Different Diameters. 
Diameter of valve in inches. Area of valve in square inches. 

i or 0.5 13-64 or 0.19635 

i or 0.625 5-16 or 0.30680 

f or 0.75 7-16 or 0.44179 

i or 0.875 19-32 or 0.60132 

1 25-32 or 0.7854 

li or 1.25 1 15-64 or 1.2272 

li or 1.5 1 49-64 or 1.7671 

If or 1.75 2 13-32 or 2.4053 

2 3 9-64 or 3.1416 

2i or 2.5 4 29-32 or 4.9087 

3 7 1-16 or 7.0686 

3i or 3.5 9 5 8 or 9.6211 

4 12 9-16 or 12.5664 

4i or 4.5 15 29-32 or 15.9043 



104 ENGINEERING. 



Diameter of valve in inches. Area of valve in square inches. 

5 19 41-64 or 19.635 

5i or 5.5 23 49-64 or 23.7583 

6 ...28 9-32 or 28.2744 

B. 

Valve, Safety, Hints concerning the. — Some convenient ar- 
rangement, such as a cord or lever, should be fitted to a safety- 
valve, so that it can readily be opened by hand ; and the valve 
should be moved at least once a day, to keep it in good working 
order. A simple experiment to determine whether or not the 
valve is in truth a safety valve can readily be made by every 
steam-user. It will only be necessary to shut off the steam from 
the engine, or wherever else it is used, and making up a good 
fire in the boiler, observe whether the pressure increases materi- 
ally beyond the point for which the valve is set. This experiment 
can be made without the slightest danger, since, if the valve 
will not relieve the boiler automatically, it can be opened to any 
desired extent by hand. Any one can readily perceive the im- 
portance of making this test, for with a good safety-valve in 
working order, the chances of a disastrous boiler explosion are 
greatly diminished. B. 

Valve, Safety, Proper diameter, in inches, for a. — This de 
pends upon (1) the steam-pressure to which the valve is ex- 
posed ; (2) the lift of the valve ; (3) the quantity of steam that 
must be discharged in a given time, in order to prevent an in- 
crease of pressure. These quantities having been determined, it 
is necessary to calculate (1) the area of opening required in order 
to discharge the given quantity of steam ; (2) the diameter of a 
valve that will afford the required area of opening with the 
given lift. 

The method of making these calculations is explained below. 

A. The area of opening, in square inches, required, in order that 
a safety-vaUe may prevent the increase of steam -pressure beyond a 
given point. 

{a) For stationary and marine boilers with natural draft : Take 
the product of (1) the area of the grate-surface in square feet, and 
(2) 2.63, and divide this product by the steam-pressure as shown 
by gauge, increased by 14.7. 

(6) For stationary and marine boilers with forced draft : Take 
the product of (1) the area of the grate surface in square feet, 
and (2) 4.08, and divide this product by the steam-pressure as 
shown by gauge, increased by 14.7. 

(c) For locomotive boilers : Take the product of (1) the area 
of the grate-surface in square feet, (2) 11.67, and divide this 
product by the steam-pressure as shown by gauge, increased by 
14.7. 

To illustrate the rules, suppose that the steam-pressure in a 
locomotive boiler is 150 lbs. by gauge ; what is the proper area of 
opening for the escape of steam by the safety-valve, the grate- 
surface being 16 square feet ? 

The product of 16 and 11.67 is 186.72, and* the quotient arising 
from dividing this by the sum of 150 and 14.7, or 164.7, is about 
ln?o square inches, which is the required area of opening. 



ENGINEERING. 



105 



B. Tlie diameter of valve, in inches, required, to afford the neces- 
sary area of opening with the given lift. 

(a) When the lift of the valve is equal to or less than the 
depth of the seat : Diminish the required area of opening by the 
product of (1) the square of the lift, in inches ; (2) the square 
of the sine of the angle of bevel of the valve ; (8) the cosine of 
the angle of bevel of the valve, and (4) 3.1416. Divide this 
difference by the product of (1) the lift in inches ; (2) the sine of 
the angle of bevel of the valve, and (3) 3.1416. 

(6) When the lift of the valve is greater than the depth of 
the seat : Diminish the required area of opening by the product 
of (1) the square of the depth of seat, in inches ; (2) the square 
of the sine of the anprle of bevel of the valve ; (3) the cosine of 
the angle of bevel of the valve, and (4)3.1416. Divide this 
difference by 3.1416 times the sum of (1) the depth of seat in 
inches, multiplied by the sine of the angle of bevel of the valve, 
and (2) the difference between the lift and the depth of seat, in 
inches. 

A table of sines and cosines of angles from 20° to 50° will be 
found below, and an example is appended in illustration of the 
rules. 



Angle. 


Sine. 


Cosine. 


Angle. 


Sine. 


Cosine. 


20° 


.342 


.940 


36° 


.588 


.809 


21°' 


.358 


.934 


! 37° 


.602 


.799 


22° 


.375 


.927 


38° 


.616 


.788 


28° 


.391 


.921 


39° 


.629 


.777 


24° 


.407 


.914 


40° 


.643 


.766 


25° 


.423 


.906 


41° 


.656 


.755 


26° 


.438 


.899 


• 42° 


.669 


.743 


27° 


.454 


.891 


43° 


.682 


.731 


28° 


.469 


.883 


44° 


.695 


.719 


29° 


.485 


.875 


45° 


.707 


.707 


30° 


.500 


.866 


46° 


.719 


.695 


31° 


.515 


.857 


47° 


.731 


.682 


32° 


.530 


.848 


48° 


.743 


.669 


33° 


.545 


.839 


49° 


.755 


.656 


34° 


.559 


.829 


50° 


.766 


.643 


35° 


.574 


.819 


i 







Example. — A safety-valve has a bevel of 33°, a depth of seat of 
J inch, and is required to give an area of opening of 2 inches, 
with a lift of ^ inch. What should be its diameter ? 

Square of depth of seat 0.0625 

Square of sine of 33^ 0.297 

Product 0.019 

Cosine of 33° 0.839 

Product 0.016 



106 ENGINEERING. 

Product (brought forward) 0.016 

Multiply by 3.1416 

Product 0.05 

Area of opeuing 2.00 in. 

Subtract 0.05 

Difference is 1.95 

Depth of seat 0.25 

Sine of 33° 0.545 

Their product 0.136 

Multiply by 3.1416 

Product 0.427 

Lift 0. 50 

Subtract depth of seat 0.25 

The difference is 0.25 

Multiply by 3.1416 

And the product is 0. 785 

Add 0.427 



1.212 
Now 1.95 divided by 1.212 gives the diameter of valve, 1.61 
inches, nearly. B. 

Valve, Safety, Proportions of parts of. — 1st. To find the 'pres- 
sure per square inch at which a given valve will open. Measure the 
following distances horizontally from the fulcrum to (1) the 
centre of the valve-stem ; (2) the centre of the weight ; (3) the 
centre of gravity of the lever, or the point on which it will bal- 
ance if placed upon a knife-edge. Measure the diameter of the 
valve, and determine its area, either from a table or by multiply- 
ing the square of the diameter by 0.7854. Find the weight of 

(1) the valve ; (2) the lever ; (3) the ball. Multiply (1) the 
weight of the ball by its horizontal distance from the fulcrum ; 

(2) the weight of the lever by its horizontal distance from the 
fulcrum ; (3) the weight of the valve by its horizontal distance 
from the fulcrum ; (4) the area of the valve by its horizontal 
distance from the fulcrum. Add together the first three products 
and divide the sum by the fourth product. 

Example. — A given safety-valve has a weight of 50 lbs. 24 
inches from the fulcrum, the lever weighs 6 lbs., and its centre of 
gravity is 15 inches from the fulcrum ; the weight of the valve 
is 2 lbs., and its centre is 4 inches from the fulcrum. The dia- 
meter of the valve is 2 inches. At what pressure will the valve 
begin to rise ? 

Square of diameter 4 

Multiply by 0.7854 

Area of valve in square inches 3.1416 

(1) 50 times 24 is 1200 ; (2) 6 times 15 is 90 ; (3) % times 4 is 



8 ; (4) 4 times 3.1416 is 12.5664. The sum of (1), (2), and (3) is 
1298, wliicli divided by 12.5664 (tlie fourth product) is 103.03, 
the pressure in lbs. per square inch at which the valve will open. 
2d. To find where to 'place the loeight on a safety-valve so that it 
shall open at a given pressure of steam. Multiply (1) the weight 
of the lever by the horizontal distance of its centre of gravity 
from the fulcrum ; (2) the weight of the valve by its horizontal 
distance from the fulcrum ; (3) the area of the valve by tlie 
pressure of steam in lbs. per square inch, and by the horizontal 
distance of the valve from the fulcrum. Add together the first 
two products, subtract their sum from the third product, and di- 
vide the difference by the weight of the ball. 

Example. — The ball of a safety-valve weighs 100 lbs., the 
lever weighs 10 lbs., the valve weighs 2 lbs., and has a diameter 
of 3 inches. The distance of the centre of gravity of the lever 
from the fulcrum is 25 inches, and the distance of the centre of 
the valve from the fulcrum is 5 inches. How far from the ful- 
crum must the valve be placed, in order that the lever may open 
at a pressure of 100 lbs.? 

Area of valve, 7.07 square inches. 

(1) 10 times 25 is 250 ; (2) 2 times 5 is 10 ; (3) the product of 
7.07, 100, and 5, is 3535. Adding together products (1) and (2), 
we have as their sum 260 ; subtracting this from 3535, the third 
product, we have 3275. Dividing this difference by 100, the 
weight of the ball, we have 32.75, or 32f inches as the distance 
from fulcrum to ball. 

To find what diameter a safety-valve must have, the other parts be- 
ing known to open at a given steam-ptressure. Multiply (1) the weight 
of the ball by its horizontal distance from the fulcrum ; (2) the 
weight of the lever by the horizontal distance of its centre of 
gravity from the fulcrum ; (3) the weight of the valve by the 
horizontal distance of its centre from the fulcrum ; (4) the pres- 
sure of steam in pounds per square inch by the horizontal dis- 
tance of the valve from the fulcrum, and by the number 0.7854. 
Add together the first three products, divide their sum by the 
fourth product, and take the square root of the quotient. 

Example. — Weight of ball, 60 lbs. ; lever, 7 lbs. ; valve, 3 lbs. 
Distances from fulcrum : ball, 30 inches ; centre of gravity of 
lever, 16 inches ; centre of valve, 3 inches. Pressure of steam, 
70 lbs. per square inch. What should be the diameter of the 
valve ? 

(1) The product of 60 and 30 is 1800 ; (2) the product of 7 and 
16 is 112 ; (3) the product of 3 and 3 is 9 ; (4) the product of 70, 
3, and 0.7854 is 164.934. The sum of the first three products, 
1800, 112, and 9, is 1921. Dividing this sum by 164.934 (the 
fourth product), we have 11.647 inches. The square root of this 
number is 3.41 -H inches, which by the rule is the required dia- 
meter of the valve. B. 

Valve, To find the angle of bevel of a. — This is the angle of 
inclination /c <x, or e db, to sl vertical line. Make the following 
measurements : (1) greatest diameter, g 7i, of valve, in inches ; 
(2) least diameter, a b, of valve, in inches ; (3) depth, a k, of 
valve, in inches. Divide the difference of the greatest and least 



108 



ENGINEERING. 



diameters by tlie depth of seat. Find the angle whose tangent is 
nearest this quotient, in the accompanying table of tangents. 




C d 

Table of Tangents from 20° to 50' 



Angle. 


Tangent. 


1 

Angle. 


Tangent. 


20° 


.364 


36° 


.727 


21° 


.384 


37° 


.754 


22° 


.404 


38° 


.781 


23° 


.424 


39° 


.810 


24° 


.445 


40° 


.839 


25° 


.466 


41° 


.869 


26° 


.488 


42° 


.900 


27° 


.510 


43° 


.933 


28° 


.532 


44° 


.966 


29° 


.554 


45° 


1.000 


30° 


.577 


46° 


1.036 


31° 


.601 


47° 


1.072 


32° 


.625 


48° 


1.111 


33° 


.649 


49° 


1.150 


34° 


.675 


50° 


1.192 


35° 


.700 







Example. — The greatest and least diameter of a valve are 
4 6-10 and 4 inches, respectively, and the depth is i inch. What 
is the bevel ? 

Greatest diameter 4.6 

Least diameter 4. 



2)0.6 
0.5)0.3 



Tangent of angle of inclination 0.6 

From the table, it appears that the angle corresponding to this 
is nearly 31°. B. 

Valve, To find the area of opening, in square inches, of a, 
due to a given lift. — {ri) When the lift of the valve is equal 



ENGINEEKING. 109 



or to less than the depth of seat : Find the product of (1) the 
diameter of the valve, in inches ; (2) the lift, in inches ; (3) the 
sine of the angle of bevel of the valve, and (4) 3.1416. Add this 
to the product of (1) the square of the lift, in inches ; (2) the 
square of the sine of angle of bevel of the valve ; (3) the cosine 
of the angle of bevel of the valve, and (4) 3.1416. 

(6) When the lift of the valve is greater than the depth of 
seat : Find the product of (1) the diameter of the valve, in 
inches ; (2) the depth of seat, in inches ; (3) the sine of the angle 
of bevel of the valve, and (4) 3.1416. Find the product of (1) 
the square of the depth of seat, in inches ; (2) the square of the 
sine of the angle of bevel of valve ; (3) the cosine of the angle 
of bevel of valve, and (4) 3.1416. Find the product of (1) the 
diameter of the valve, in inches ; (2) the difference betvi^een the 
lift and the depth of seat, in inches, and (3) 3.1416. Take the 
sum of these three products. 

Example. — The diameter of a valve is 4 inches, the bevel is 35°, 
and the depth of seat J of an inch. What is the area of open- 
ing for a lift of | of an inch ? 

The product of 4, 0.25, 0.574 (the sine of 35°), and 3.1416 is 
1.8. 

The product of the square of 0.25, the square of 0.574, 0.819, 
(the cosine of 35°), and 3.1416 is 1.85. 

The product of 4, 0.125 (the difference between the lift and 
depth of seat), and 3.1416 is 1.57. 

The sum of 1.8, 1.85, aad 1.57 is 3.42 square inches, the area 
of opening required. B. 



BELTS, PULLEYS, AND SHAFTING. 

Belt-Holes, Laying out, through floors. — If a belt is to be 
carried from a pulley on an overhead shaft to one on any floor 
above, the distance from centre of lower shaft to ceiling — under 
side of floor — should be measured and noted ; then the thickness 
of floor ; next the distance between top of floor and centre of 
upper shaft. If one pulley or shaft is directly over the other, 
the size of pulleys and width of belt being known, you have all 
the data necessary if you measure the distance of one shaft 
from the wall of building, which is done by dropping a plummet 
from centre of shaft or diameter of pulley, and measuring to the 
wall from that point. From these data, whether the two shafts 
are in the same vertical plane, whether the diameters of the pul- 
leys are equal, and whether the belt is to be carried through one, 
two, three, or even four floors or not, the intelligent mechanic can 
lay out a diagram that will enable him to cut his belt-holes ac- 
curately. The diagram may be laid out fall-size on a swept 
floor, or, on a reduced scale, on a board or sheet of paper. Mea- 
sures thus made can easily be transferred to the floor through 
which the holes are to be made. 



110 ENGINEERING. 

Belt-Lacing, Eel-skin. — A mill-owner says : '' Eel-skins 
make the best possible strings for lacing belts. One lace will 
outlast any belt, and will stand wear and hard usage where 
hooks or any other fastenings fail. Our mill being on the bank 
of the river, we keep a net set for eels, which, when wanted, are 
taken out in the morning and skinned, and the skins are stuck on 
a smooth board. When dry, we cut them in two strings, making 
the eel-skin, in three hours from the time the fish is taken from 
the water, travel in a belt. " 

Belt-Lacings, Holes for. — The strain on belts is always in the 
direction of their length, and therefore holes cut for the reception 
of lacing should be oval (the long diameter in line with the 
belt). In butting or meeting belts, the crossings of the lacings 
should be on the outside. 

Belt passing over two Pulleys, To find the length of a. — 
Measure the distance between the centres of the pulleys, the 
diameters of the pulleys, and the thickness of the belt. Add the 
thickness of the belt to the diameter of a pulley, and this gives 
the effective diameter. Half this is the effective radius, and it 
is to be noted that the effective radius, or the effective diameter, 
of a pulley should generally be used in all calculations relating 
to belts and pulleys. In making such calculations, care must be 
taken, also, to have all the dimensions in the same unit, feet or 
inches. In general, it is well to reduce all dimensions to feet. 

To illustrate the preceding remarks, suppose that the diame- 
ter of a pulley is 10 inches, and that the thickness of the belt 
passing over it is f of an inch. What is the effective radius, in 
feet ? Arts. The effective diameter is lOf inches ; hence the effec- 
tive radius is 5-^6 inches. 5 inches is 0.417 ft. -^^ of an inch is 
0.016 ft. Hence 5^^^ inches is 0.433 ft. 

There are two cases to be considered, one in which the belt is 
crossed, and the other in which it is open. 

To find the length of a crossed belt passing over two pulleys : 

(1) Divide the sum of the radii of the two pulleys by the dis- 
tance between their centres, and find from the table of factors the 
factor corresponding to this quotient. 

(2) Multiply the factor so found by the sum of the radii. 

(3) Multiply the sum of the radii by the number 3.1416. 

(4) Subtract the square of the sum of the radii from the 
square of the distance between centres, and take the square root 
of the remainder. Multiply the quantity so obtained by 2. 

(5) Take the sum of the quantities obtained by (2), (3), and (4). 
Example. — The radius of one pulley is 42 inches, of the other 

36 ; the distance between centres of pulleys is 12 feet, and the 
thickness of the belt is i of an inch ; required, the length of the 
belt. 

The effective radii are 3.51 feet and 3.01 feet. 

(1) Sum of radii, 6.520. Distance between centres, 12. Quo- 
tient of first quantity divided by second, 0.54. Factor in table 
corresponding to this quotient, 1.141. 

(2) 1.141 multiplied by 6.52, 7.439 + . 

(3) 6.541 multiplied by 3. 1.416. 20. 483-1- • 



ENGINEEEING. 



Ill 



(4) Square of distance between centres 144. 

Square of sum of radii. . . 42.51 



Difference 101.49 

Square root of difference, 10.074 + . 10.062 multiplied by 2, 

20.148. 

(5) Sum of 7.439, 20.483, and 20.148, 48.07 feet, or 48 feet and 

§^ of an incli, length of belt required. 



TaUe 


of Factors , 


for Determining the 


Length of 


Belts. 


Quotient. 


Factor. 


Quotient. 


Factor, j 


Quotient. 


Factor. 


0.01 


0.020 


0.35 


0.716 


0.69 


1.523 


0.02 


0.040 


1 0.36 


0.737 


0.70 


1.551 


0.03 


0.060 


\ 0.37 


0.758 ' 


0.71 


1.580 


0.04 


0.080 


0.38 


0.780 i 


0.72 


1.608 


0.05 


0.100 


i 0.39 


0.802 


0.73 


1.637 


0.06 


0..120 


0.40 


0.823 


1 0.74 


1.666 


0.07 


0.140 


i 0.41 


0.845 


0.75 


1.696 


0.08 


0.161 


1 0.42 


0.867 


0.76 


1.727 


0.09 


0.180 


i 0.43 


0.890 


0.77 


1.758 


0.10 


0.201 


j 0.44 


0.912 


0.78 


1.790 


0.11 


0.220 


0.45 


0.934 


0.79 


1.822 


0.12 


0.241 


0.46 


0.956 


0.80 


1.855 


0.13 


0.261 


0.47 


0.979 


0.81 


1.888 


0.14 


0.281 


0.48 


1.002 


0.82 


1.923 


0.15 


0.301 


0.49 


1.025 


0.83 


1.958 


-0.16 


322 


0.50 


1.047 


0.84 


1.995 


0.17 


0.342 


0.51 


1.070 


0.85 


2.032 


0.18 


0.362 


0.52 


1.094 


0.86 


2.071 


0.19 


0.383 


0.53 


1.118 


0.87 


2.111 


0.20 


0.403 


0.54 


1.141 


0.88 


2.152 


0.21 


0.424 


0.55 


1.165 


0.89 


2.195 


0.22 


0.444 


0.56 


1.189 


0.90 


2.240 


0.23 


0.464 


0.57 


1.214 


0.91 


2.287 


0.24 


0.485 


0.58 


1.238 


0.92 


2.336 


0.25 


0.506 


0.59 


1.262 


0.93 


2.389 


0.26 


0.527 


0.60 


1.287 


0.94 


2.446 


0.27 


0.547 


0.61 


1.312 


0.95 


2.507 


0.28 


0.568 


0.62 


1.338 


0.96 


2.574 


0.29 


0.589 


0.63 


1.364 


0.97 


2.651 


0.30 


0.610 


0.64 


1.389 


0.98 


^2.743 


0.31 


0.631 


0.65 


1.415 


0.99 


2.859 


0.32 


0.652 


0.66 


1.443 


: 1.00 


3.142 


0.33 


0.673 


0.67 


1.469 


.... 




0.34 


0.694 


0.68 


1.496 







To find the length of an open belt passing over two pulleys : 
(1) Divide the difference of the radii by the distance between 



112 ENGINEERING. 

centres, and find from tlie table of factors the factor correspond- 
ing to this quotient. 

(2) Multiply the factor so found by the difference of the radii. 

(3) Multiply the sum of the radii by the number 3.1416. 

(4) Subtract the square of the difference of the radii from the 
square of the distance between centres, and take the square root 
of the remainder. Multiply the quantity so obtained by 2. 

(5) Take the sum of the quantities obtained by (2), (3), and (4). 
It will be observed that these rules require only simple arith- 
metical operations. 

Example. — Griven, diameter of driving-wheel, 36 inches ; of 
driven wheel, 9 inches ; distance between centres, 5 feet ; thick- 
ness of belt, i of an inch ; what is the length of the belt ? 

Effective radii, 1.505 and 0.380 feet. (1) Difference of radii, 
1.125. Distance between centres, 5. Quotient, 0.23. Factor in 
table corresponding to this quotient, 0.464. (2) 0.464 multiplied 
by 1.125, 0.522. (3) Sum of radii, 1.885. 1.885 multiplied by 
3.1416, 5.922. 

(4) Square of distance between centres 25. 

Square of difference of radii 1.266 

Difference 23.734 

Square root of difference, 4.872. 4.872 multiplied by 2, 9.744. 
(5) Sum of 0.522, 5.922, and 9.744, 16.188 feet, or 16 feet 2 J 
inches, length of belt. B. 

Belts, Power transmitted by leather. — By the aid of the ac- 
companying tables, now published for the first time, it will be 
easy for any one to ascertain the amount of power that can be 
safely transmitted by good leather belts under ordinary circum- 
stances. It is scarcely necessary to add that the power trans- 
mitted by a belt in any special case can only be ascertained by 
experiment. All that can be done by the most elaborate rules is 
to show what power ought to be transmitted if a belt is properly 
arranged. The tables and accompanying rules will be useful, 
therefore, in calculations of the width of belt required to do a 
definite amount of work under given circumstances. With 
these preliminary explanations, the use of the tables will be 
illustrated. 

I. Other things being equal, the power transmitted by a belt de- 
pends upon the arc of contact and the speed of the belt. 

II. I'o find the arc of contact between a belt and a pulley, by the 
aid of the accompanying table. 

First Method. — Measure the length of the portion of the cir- 
cumference of the pulley that is in contact with the belt, and 
the diameter of the pulley. Divide the first measurement by the 
radius of the pulley, which gives the length of the arc of contact 
for a circle whose radius is 1. Find the number nearest to this 
in the column of the table headed ''Length of arc for a radius 
of 1," and the required angle will be found in the same hori- 
zontal line of the next column, to the left, headed " Arc of con- 
tact. " 



ENGINEERING. 



113 



Table for Finding the Arc of Contact of a Belt with a Pulley. 



Both pulleys, crossed belt, and 
large pulley, open belt. 


Small pulley, open belt. 


Arc of contact. 


Length of arc for 
a radius of 1. 


Arc of contact. 


Length of arc for 
a radius of 1. 


180° 


3.142 


180° 


3.142 


181° 


3.162 


179° 


3.122 


■ 182° 


3.182 


178° 


3.102 


183° 


3.202 


177° 


3.082 


185° 


3.222 


175° 


3.062 


186° 


3.242 


174° 


3.042 


187° 


3.262 


173° 


3.022 


188° 


3.282 


172° 


3.002 


189° 


3.303 


171° 


2.981 


190° 


3.322 


170° 


2.962 


192° 


3.343 


168° 


2.941 


193° 


3.362 


167° 


2.922 


194° 


3.383 


166° 


2.901 


195° 


3.403 


165° 


2.881 


196° 


3.423 


164° 


2.861 


197° 


3.443 


163° 


2.841 


198° 


3.464 


162° 


2.820 


200° 


3.484 


160° 


2.800 


201° 


3.504 


159° 


2.780 


202° 


3.525 


158° 


2.759 


203° 


3.545 


157° 


2.739 


204° 


3.566 


156° 


2.718 


205° 


3.586 


155° 


2.698 


207° 


3.606 


153° 


2.678 


208° 


3.627 


152° 


2.657 


209° 


3.648 


151° 


2.636 


210° 


3.669 


150° 


2.615 


211° 


3.689 


149° 


2.595 


213° 


3.710 


147° 


2.574 


214° 


3.731 


146° 


2.553 


215° 


3.752 


145° 


2.532 


216° 


3.773 


144° 


2.511 


217° 


3.794 


143° 


2.490 


219° 


3.815 


141° 


2.469 


220° 


3.836 


140° 


2.448 


221° 


3.858 


139° 


2.426 


222° 


3.879 


138° 


2.405 


223° 


3.900 


137° 


2.384 


225° 


3.922 


135° 


2.362 


226° 


3.944 


134° 


2.340 


227° i 3.965 


133° 


2.319 


228° 3.987 


132° 


2.297 


230° 4.009 


130° 


2.275 


231° 1 4.032 


129° 


2.252 


232° 4.054 


128° 


2.230 


234° ! 4.0T6 


126° 


2.208 


235° I 4.098 


125° 


2.186 


236° i 4.121 


124° 


2.163 


237° 1 4.144 


123° 


2.140 


239° I 4.167 


121° 


2.117 


240° 


4.189 


120° 


2.095 



114 



ENGINEERING. 



Table for Finding the Arc of Contact of a Belt with a Pulley. 

{Continued) 



i 


Both pulleys, crossed belt, and 
large pulley, open belt. 


Small pulley, open belt. 


55 
< 

8 


Arc of contact. 


Length of arc for 
a radius of 1. 


Arc of contact. 


Length of arc for 
a radius of 1. 


.51 


241° 


4.212 


119° 


2.072 


.52 


243° 


4.236 


117° 


2.048 


.53 


244° 


4.260 


116° 


2.024 


.54 


245° 


4.283 


115° 


2.001 


.55 


247° 


4.307 


113° 


1.977 


.56 


248° 


4.331 


112° 


1.953 


.57 


250° 


4.356 


110° 


1.928 


.58 


251° 


4.380 


109° 


1.904 


.59 


252° 


4.404 


108° 


1.880 


.60 


254° 


4.429 


106° 


1.855 


.61 


255° 


4.454 


105° 


1.830 


.62 


257° 


4.480 


103° 


1.804 


.63 


258° 


4.506 


102° 


1.778 


.64 


260° 


4.531 


100° 


1.753 


.65 


261° 


4.557 


99° 


1.727 


.66 


263° 


4.585 


97° 


1.699 


.67 


264° 


4.611 


96° 


1.673 


.68 


266° 


4.638 


94° 


1.646 


.69 


267° 


4.665 


93° 


1.619 


.70 


269° 


4.693 


91° 


1.591 


.71 


271° 


4.722 


89° 


1.562 


.72 


272° 


4.750 


88° 


1.534 


.73 


274° 


4.779 


86° 


1.505 


.74 


275° 


4.808 


85° 


1.476 


.75 


277° 


4.838 


83° 


1.446 


.76 


279° 


4.869 


81° 


1.415 


.77 


281° 


4.900 


79° 


1.384 


.78 


283° 


4.932 


77° 


1.352 


.79 


^ 284° 


4.964 


76° 


1.320 


.80 


286° 


4.997 


74° 


1.287 


.81 


288° 


5.030 


72° 


1.254 


.82 


290° 


5.065 


70° 


1.219 


83 


292° 


5.100 


68° 


1.184 


.84 


294° 


5.137 


66° 


1.147 


.85 


296° 


5.174 


64° 


1.110 


.86 


299° 


5.213 


61° 


1.071 


.87 


301° 


5.253 


59° 


1.031 


.88 


303° 


5.294 


57° 


0.990 


.89 


306° 


5.337 


54° 


0.947 


.90 


308° 


5.382 


52° 


0.902 


91 


311° 


5.429 


49° 


0.855 


.92 


314° 


5.478 


46° 


0.806 


.93 


317° 


5.531 


43° 


0.753 


.94 


320° 


5.588 


40° 


0.696 


.95 


324° 


5.649 


36° 


0.635 


.96 


328° 


5.716 


32° 


0.568 • 


.97 


332° 


5.793 


28° 


0.491 


.98 


337° 


5.885 


23° 


0.399 


.99 


344° 


6.001 


16° 


0.283 


1.00 


360° 


6.284 


0° 


0.000 



ENGINEERING. 115 



Example. — Suppose the length of the circumference of a pul- 
ley in contact with a belt is 8^ feet, and the diameter of the 
pulley is 4 feet. The quotient arising from dividing 8|^ by 2 (the 
radius of the pulley) is 4.25, and the number in the table nearest 
to this is 4.26, showing that the required arc of contact is about 
53°. 

[It is to be noted that, in calculations of this kind, the effective 
radius of the pulley should be used (see page 110), and all dimen- 
sions must be referred to the same unit of measurement.] 

Second Method. — Measure the effective diameters of both pul- 
leys, and the distance between their centres. There are two 
cases to be considered : 

(a) To find the arc of contact for a crossed belt. 

Divide the sum of the radii of the two pulleys by the distance 
tween their centres ; find in the column of constants the nearest 
number to the quotient, and pick out the corresponding angle. 

Example. — Diameter of driven pulley, 20 inches ; of driving 
pulley, 24 ; distance between centres, 8 feet. What is the arc of 
contact on each pulley of a crossed belt passing over them ? Sum 
of radii, 1.8333 feet. 1.8333 divided by 8 is 0.23, nearly. From 
the table, it appears that the angle required is 207°. 

(b) To find the arc of contOjCt for an open belt. 

Divide the difference of the radii of the two pulleys by the 
distance between their centres, and find the angles corresponding 
to the constant nearest to the quotient, in the table. 

Example. — In the case of an open belt passing over two pul- 
leys, the following dimensions are given : Diameter of driving 
pulley is 5.25 feet; diameter of driven pulley is 3.5 feet; dis- 
tance between centres is 9 feet. The difference of radii (0.875) di- 
vided by 9 is 0.097-j-. Nearest constant in table, 0.1, correspond- 
ing to an angle of contact of 192° on the driving, and 168° on the 
driven pulley. 

[These rules are founded on the assumption that the belt is 
drawn perfectly tight between the pulleys. Where there is much 
deviation from this, in practice, it is better to employ the first 
method.] 

III. To find the speed of a belt, infect, per minute. 

Multiply the diameter of either pulley, in feet, by 3.1416 times 
the number of revolutions that it makes per minute. 

Example. — A belt passes over a pulley that is 3 feet in diame- 
ter, and makes 200 revolutions a minute. The speed of the belt 
is the product of 3, 3.1416, and 200, or about 1885 feet per 
minute. 

IV. To find the power that can be safely transmitted by a good 
leather belt of given width, passing over smooth iron pulleys, and 
running at a given speed, the arc of contact being also given. 

This is determined by means of the second table. Find the 
horse-power for a belt one inch in width, for the nearest arc of 
contact in the table, and the nearest speed of belt, and multiply 
this by the width of the belt. If the belt is open, and the pul- 
leys have different diameters, take the angle of contact made by 
the belt with the smaller pulley. 



116 



ENGINEERING. 









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ENGINEERING. 



119 



Example. — What horse-power can be transmitted by a leather 
belt 10 inches wide, making an angle of contact of 80° with the 
smaller of the two pulleys over which it passes, and having a speed 
of 2400 feet per minute? Ans. — Horse-power for a belt 1 inch 
wide and 2000 feet speed is 1.802 ; horse-power for a belt 1 inch 
wide and 400 feet speed is 0.360 ; therefore, by addition, horse- 
power of 1 inch belt for 2400 feet speed is 2.162; and for 10 horse- 
power, 10 times 2.162, or 21.62. 

V. To find the width of belt necessary to transmit a given 
imfiount of power for a given arc of contact and given speed in 
feet per minute. 

Find the power transmitted by a belt 1 inch wide, and divide 
the given power by this amount. 

Example. — An open belt passes over two pulleys having dia- 
oieters of 4 and 6 leet respectively, and the former makes 300 
revolutions a minute. The distance between the centres of the 
pulleys is 15 feet. What should be the width of a belt to trans- 
mit 50 horse-power under these circumstances ? Speed of belt 
in feet per minute, 3770 ; arc of contact of belt with smaller 
pulley, 172° ; horse-power transmitted by a belt 1 inch wide, 
under conditions in table nearest to those determined above (i.e. , 
for arc of contact of 170°, and speed of 3800), 5.488. Required 
width of belt, 50 divided by 5.488, or a little over 9 inches. 

VI. In the use of a leather belt, it is best to run it with the 
grain side next to the pulleys, or in exactly the opposite way 
from that in which the hide was worn by the animal that was 
:he original proprietor of the leather. 

VII. Lace-leather is better than hooks for fastening the ends 
of a belt together ; and a still better method, after a belt has be- 
come sufficiently stretched by use, is to rivet the ends together 
ivith long laps. In lacing a belt of any considerable size, make 
:wo rows of holes in each belt end, and put in double lacing. 

VIII. A belt that is made of good material, and is of ample 
jize, will last for many years, if kept clean, and prevented from 
Decoming dry and hard by the use of neat's-foot oil. It is poor 
economy to buy a belt whose chief recommendation is its small 
irst cost. It is also a bad plan to use a belt that is just sufficient 
:o transmit the power when very tightly strained. B. 




CORNER-TUBNED BELT. 



Belts, Corner-turned, Device for. — The two shafts placed at 
right angles, as shown in the engraving, carry the belt from A or 



120 



ENGINEERING. 



B, passing around two flanged pulleys or guides, C, turning loose- 
ly oil a fixed upright shaft, and sustained in position by a collar 
under the hub of each. It is possible to run pulleys by this de- 
vice which not only have varying diameters, but the shafts of 
which are on different levels ; but the results are not so good, 
owing to unequal strain on the belt. It is better to confine this 
method to shafts on the same level, and to pulleys of equal dia- 
meter, and the useful limit of angle of shafts is that oi 45°, or 
less. A greater or more obtuse angle is better run by means of 
guides on two uprights. 



Belts, Coupling. — In Fig. 1, A, 
16 sheet-iron, riveted to the ends 
shown in the natural size in Fig. 2, 



B, C, and D are pieces of No. 
of the belt ; E K are hooks, 
riveted to B. After the belt 




COUPLING BELTS. 



is laid over the pulleys, the hooks, F and G, of the lever, shown 
in Fig. 3, are placed in the holes at C and D. Now the two ends 
of the belt are drawn together by the lever, H, and the hooks. 
E, are put in their places at A. Then the lever is taken out, 
leaving the joint finished. By this method, two men can set and 
couple a belt in the least possible time, obtaining an effectual 
joint, which will never allow the belt to run out of true, or to re- 
Verse. 

Belts, Increasing the conveying force of. — Adding to the width 
of a belt and of the faces of the pulleys increases immensely the 
power of conveying force. A wide belt is always better than a 
narrow one strained to its utmost capacity. 

Belts, Mending.— Lay the two ends of the belt exactly even, 
with the insides together, and punch one straight row of holes- 
across the end, driving the punch through both pieces so that the 



ENGINEERING. 121 



holes may correspond. Now take your lace, pointed at both 
ends, and pass the points in opposite directions through the first 
hole, still keeping the two ends of the belt together as when 
punched, and draw the loop tight, observing to keep the ends of 
equal length. Pass the points through the second hole, and so 
proceed to the last ; then tie the ends over the edge of the belt, 
and the job is done. A belt can thus be mended in half the time 
and with half the length of lacinor required in the usual way ; and 
when the belt is subjected to heavy strains or slipping, it will 
wear ten times as long, as the lace never touches the pulley- 
faces. Of course the plan is not applicable when both sides of a 
belt run over pulleys, nor when the projecting ends would strike 
any thing in their track. 

Belts, Oiling. — The best mode of oiling a belt is to take it 
from the pulleys, and immerse it in a warm solution of tallow and 
oil ; after allowing it to remain a few moments, the belt should 
be immersed in water heated to 100° Fahr., and instantly removed. 
This will drive the oil and tallow all in, and at the same time 
properly temper the leather. 

Belts, Rubber, To prevent, slipping on pulleys. — Chalk the 
pulley when slipping occurs. The presumption is, however, that 
the belt is either too narrow or too loose. 

Belts, Splicing large. — Cut your belt perfectly square on the 
ends and to the proper length ; then cut a piece of belt of the 
same width and thickness, about 3 feet long. Bring the ends of 
the belt together, and put the short piece on the back of the 
joint, or outside, and bolt the belt and piece together with what 
are known as elevator- bolts, used for fastening the buckets to 
elevator-bands. The tools required are a brace and bit to bore 
the holes, and a small pair of blacksmith's tongs to tighten up the 
nuts with. 

Belts, Testing leather for. — A cutting of the material about 
0.03 of an inch in thickness is placed in strong vinegar. If the 
leather has been thoroughly acted upon by the tanning, and is 
hence of good quality, it will remain, for months even, immersed 
without alteration, simply becoming a little darker in color. But, 
on the contrary, if not well impregnated by the tannin, the 
fibres will quickly swell, and, after a short period, become trans- 
formed into a gelatinous mass. 

Belts, To lay out quarter-tvrist. — To make holes through 
floors for the belts, lay out on a floor with chalk-line and train 
two views of the pulley, or by scale on paper as shown in the an- 
nexed diagram. B is the belt running in the direction of the 
arrow on the lower pulley, and C is the belt running in the 
opposite direction. Therefore, drop a plumb-line, representing 
the perpendiculars, B and C, and draw the diagonals governed by 
the diameters of the pulleys, marking the distances a h and c d 
on the floor. Now, drop a plumb-line from each side of the cen- 
tre of face of upper pulley to the floor, and from one point, c, 



122 



ENGINEERING. 



thus found, lay off the distance a &, in a line parallel with the 
upper shaft, and from the point a in the distance, c d, parallel 




LATING OUT QUARTER-TWIST BELTS THROUGH FLOORS. 

with the lower shaft. These points are the places at which the 
holes should be cut. 

Friction and Lubricants. — Whenever one surface moves 
upon another, the rough and projecting points of the two sur- 
faces (which always exist, even in the smoothest surfaces) op- 
pose resistance to the motion, and this resistance is called fric- 
tion. 



ENGINEERING. 123 

The coefficient of friction is a quantity expressing the ratio of 
the friction to the pressure. For instance, if the resistance to 
moving one piece of metal on another is one fifth of the weight of 
the moving body, the coefficient of friction in this case is one 
fifth, or 0.2. Hence, know^ing the coefficient of friction, in any 
given instance, and the weight of the body causing the resist- 
ance, the amount of friction is found by multiplying these two 
quantities together. 

The work due to or lost on account of friction, in any given 
time, is found by multiplying the amount of friction of the moving 
body by the space passed through in the given time. It is cus- 
tomary to estimate the amount of friction in pounds, to make the 
given time one minute, and to measure the distance passed 
through in that time in feet. The result obtained will then ex- 
press the number of foot-pounds of work performed per minute 
in overcoming friction, and this can readily be reduced to horse- 
power, or any other desired unit of work. It is important to 
maintain the distinction between the amount of friction and the 
work of friction. 

The experiments of Coulomb and Morin have demonstrated 
the following facts in regard to friction : 

That it is proportional to the pressure. 

With some limitations, that it is independent of the area of the 
surface pressed, and independent of the velocity of motion. 

The limitations are, that the pressure should not be so great as 
to abrade or wear away the surface rapidly, in which case the 
friction does not follow the laws enunciated above ; also, that 
the velocity of motion shall not be so great as to expel the lubri- 
cant. It is found, for instance, in the case of the journals of car- 
axles, that they require to be enlarged as the speed increases, in 
order to prevent the expulsion of the lubricant. The actual bear- 
ing surface of a journal is usually considered to be the projected 
area of that journal, or the product of the length multiplied by 
the diameter. For instance, if a journal is 4 inches in diameter 
and 7 inches long, the bearing surface is 28 square inches. 

The pressure per square inch on the bearing surface should 
not exceed the following limits : 

Velocity of periphery Limiting pressure per sq. in. 

of journal. of bearing surface. 

1 foot per second 382 lbs. 

2i feet per second 224 " 

5 feet per second 140 '* 

It is well known that one of the most common expedients for re- 
ducing the friction between two rubbing surfaces is to interpose 
some lubricant, which seems to form a coating to the projecting 
points, making the whole surface more continuous, and thus les- 
sening the resistance. At very low pressures and velocities the 
viscosity of the lubricant occasionally causes the resistance to be 
increased instead of lessened, but in general the effect of an un- 
guent is to decrease the friction in quite a large ratio. Careful 
experiments have been made with regard to the friction between 
two surfaces when they were perfectly dry and clean, and when 



124 



ENGINEERING. 



diflferent lubricants wero used. In this manner it has been found 
that good oil, such as olive-oil, is one of the best lubricants ; that 
lard is better than tallow, and that the use of water, instead of 
lessening the friction, generally increases it. Experiments upon 
the manner of applying the lubricant show that there is a great 
advantage in a continual application, so as to keep a film con- 
stantly interposed between the rubbing surfaces, over the case in 
Avhich the surfaces are merely kept slightly greasy. Below are 
given mean values for the coefficient of friction, in cases arising 
trom the sliding of one plane surface upon another, the surfaces 
being supposed to be true, and, in common language, smooth : 





Smooth surfaces with- 
out lubrication 






Wetj 


lubricated 


WITH 






Natuee of the sliding 

SURFACE. 








o 


o 

o 




p 


: 


?§ 

: ^ 

; 1 


Wood <^n wood 


0.38 
0.41 
0.18 




0.144 

0.20 

0197 


0.064 
0.071 


0.071 
0.079 
f)092 


0.066 
0.076 
0.075 




W^ood on metal 






Metal on metal 


811 


070 





















In the case of journals, the coefficient of friction is generally 
much less than for plane surfaces. Mean values of this coeffi- 
cient, both for wood and metals, vary from 0.15, when the jour- 
nal is only slightly unctuous, to 0.05, when there is a continual 
supply of the lubricant. In regard to journal-friction, the amount 
is independent of the diameter of the journal, but the work re- 
quired to overcome friction will of course be greater with a large 
than with a small journal, because the distance passed through 
by the periphery of the journal in a given time will be greater in 
the former case. B. 

Belts, Testing vulcanized rubber for.^ — These trials consist in 
examining the comparative degrees of elasticity and tenacity. 
Tlie manner in which they are conducted in the French navy ap- 
pears practical and easily followed. The first test consists in cut- 
ting from the slieets samples, which are left in a steam-boiler 
under a pressure of 5 atmospheres for 48 hours. At the end of 
this time, the pieces should not have lost their elasticity. The 
specimens may then be placed on the grating of a valve-box, un- 
der a pressure from above of 85.5 lbs. per square inch, and should 
withstand 9100 strokes at the rate of 100 per minute. Specimens 
not boiled should withstand 17,100 strokes. Thongs of rubber 
boiled, and having a section 0.6 inch square and a length of 8 
inches, fixed between supports and elongated 3.9 inches, should 
resist, without breaking, a further elongation of 8 inches, re- 



ENGINEERING. 125 



peated 22 times a minute for 24 hours. Thongs not boiled, under 
the same conditions, should resist for 100 hours. These extra 
elongations may be easily made by a wheel, to the periphery of 
which one end of the thong is fastened, while the other extremity 
may be attached to a support. By turning the wheel, any deter- 
mined elongation may be given at the rate of from 20 to 25 times 
per minute. Under the above conditions, bands of first quality 
rubber, perfectly pure and well vulcanized, break after 180 or 200 
elongations of 8 times the initial length. Bands cut from pure 
rubber, but of secondary quality, break after 50 or 60 elongations. 
Inferior caoutchouc, containing mineral matters or residue of old 
vulcanized rubber, gives no results at all. 

M. Ogier has investigated the properties of rubber belts made 
of repeated layers of cloth covered with prepared rubber. Through 
the adhesive nature of the caoutchouc, the superposed tissues 
form, after vulcanization, a homogeneous substance, comparable, 
in M. Ogier's opinion, to the best curried leather. His experi- 
ments, in order to obtain the coefficient of friction of these belts on 
cast-iron pulleys, give us results varying from 0.42 to 0.84, as 
against the coefficient for leather, 0.28. The minimum value cor- 
responds to canvas and rubber belts without an exterior rubber 
coating. On pulleys of various forms, the maximum value of the 
coefficient of friction was found on those slightly convex and pre- 
senting a roughly turned surface, this result being inverse to that 
obtained with leather belts. Similarly the presence of fatty 
bodies has an opposite action on the cloth and rubber belts to that 
which it has on leather. On covering the former with a light 
varnish of half olive-oil and half tallow, the adhesion was found 
to be considerably augmented. (1) The resistance to traction of 
rubber and canvas belts per square millimeter (0.0009 square inch) 
of section, is at least equal to that of leather belts. (2) This re- 
sistance per square millimeter is independent of dimensions—^ 
length, breadth, or thickness. Such is not the case with leather 
belts, and therefore preference should be given to rubber belting 
whenever the conditions of the power to be transmitted necessi- 
tate the employment of very long, very wide, and very thick 
belts. (3) From two trials it appears that the external covering of 
caoutchouc adds nothing to the resistance, and hence it is advan- 
tageous to use covered belts which, at equal weights and prices, 
give a superior resistance. (4) Under the same weight, the elastic 
elongation of leather belts is double that of rubber ones. The 
permanent elongation, under a change of 0.55 pound per square 
millimeter, reached 2 per cent in the former and nothing in the 
latter. 

Belts, To prevent gnawing of, by rats. — Anoint with castor- 
oil. 

Belt-Tighteners, To place. — The loss of power occasioned by 
the use of a tightener, is the power required to bend the belt under 
that pulley and to drive the pulley. By placing the tightener 
near the smaller pulley of two of unequal size, there is a greater 
loss than when it is close to the larger, since the belt requires to 
be more bent in the former case. The best place, therefore, to 



126 



ENGINEERING. 



put a tightener, is as close to the larger pulley as it can be ar- 
ranged to have it work satisfactorily. 




UNIVERSAL POINT FOR BORING-TOOL. 

Hangers, Securing.— If it should be required to place a hanger 
between flooring-beams, the floor to which it is attached should 
be strengthened with a generous piece of plank. For securing 
hangers, lag-screws are superior to bolts with nuts, where there 
is sufficient thickness of wood. A wooden straight-edge, reach- 
ing from one bearing to another, is better for leveling hangers 
and boxes than a twine, which will sag more or less. Some use 
short cylinders of iron turned to fit the box, and having a central 
hole drilled longitudinally through them. This is an excellent 
plan, as the eye may sight through, or a string be passed through 
to determine the level. Where holes are to be bored throutrh the 
floor close to a wall, post, or other vertical obstruction, a handy 
tool, similar to that shown in the cut, comes into play. It is easi- 
ly forged, and need not be finished with the elegance of contour 
shown. A is one of the yokes, and B the cross ; they are seen 
united at C. The shank o*f one yoke has a tapering square hole 
to receive a bit or auger, and the other is a tapering square shank 
to fit a stock of the bit-brace. The device is '' a universal joint," 
and can be readily worked at an angle of 45°. 

Hot-Bearing Alarm.— A cylindrical box, A, is provided with 
a perforated bottom, B, and placed directly over the journal. 
The box is filled with a prepared grease which melts at a certain 
temperature, to which it must be raised by the shaft becoming 
hot. As the compound liquifies and escapes through the perfora- 



ENGINEERING 



127 



tions, a disk, C, which rests thereon, descends, thereby tilting the 
lever, D, and so making contact between the plates, E and F. 
The latter are connected by an electric circuit with a bell which 




HOT-BEARING ALARM. 

sounds when the current is established. The pipe, G, serves for 
the ordinary lubrication of the journal. It is suggested that this 
device might be profitably used upon journals not readily acces- 
sible. 

Pulleys, Balancing. — Swing the pulley on arbors between 
lathe-centres, and note the position as determined by gravity. On 





^^^m 







^^S^^^^^^^^^^ 






^^^^^^^^^^^^ 



CONE PULLEYS, FIG. 1. 

the top side, drill and tap two holes, in which seat machine screws 
with flat heads, the shanks projecting through from the face or 



128 



ENGINEERING, 



outer side. Then, by securing pieces of iron as weights to this 
point until the pulley is balanced, the amount necessary to 
balance the pulley is found. This amount of lead is then melted 
and cast in a mould formed by clay. The screws serve to hold 
the lead in place. 

Pulleys, To design cone. — The following rules will enable any 
one who understands arithmetical operations to make the calcu- 
lations necessary for designing a set of cone pulleys in such a 
manner that the belt can be shifted from one pair to another, and 
be equally tight in every position. There are six cases to be con- 
sidered. 




CONE PULLEYS, FIG. 2. 

Case 1. — Crossed belt passing over two continuous cones, (Fig. 1.) 
— In this case, it is only necessary to use two similar conical 
drums, with their large and small ends turned opposite ways. 

Case 2. — Crossed belt passing over two stepped cones that are 
equal and opposite. (Fig. 2.) Draw vertical lines, A B, CD, etc., 
to the axes of the pulleys, at a distance apart equal to the face of 
a pulley. Lay off, on each side of the axis, distances, ab, a c, equal 
to the radius of the largest pulley, and d e, d f, equal to the radius 
of the smallest pulley. Draw a straight line, L M, through b and 
e, and N O through c and f. The points in which these lines cut 
the verticals determine the radii of the intermediate pulleys. 

Case 3. — Crossed helt passing over any two stepped cones. — As- 
sume values for the radii of one driving-pulley and the corre- 
sponding driven pulley. Then, for any assumed radius of a 



ENGINEERING. 129 

second driving-pulley, the radius of tlie driven pulley must liave 
such a value that the sum of these two radii is equal to the sum 
of the first two. The same must be true for every pair of pulleys 
in the two stepped cones. 

Example. — Suppose the radius of the first driving-pulley is 15 
inches, and of the first driven pulley 5 inches. Now, if there are 
five steps in the driving-cone, having radii of 15, 12, 9, 6, and 3 
inches respectively, the corresponding steps of the driven cone 
will have radii of 5, 8, 11, 14, and 17 inches, since the sum of the 
radii of each pair of pulleys must be equal to the sum of the 
radii of the first pair, or 20 inches. It will be evident from the 
foregoing that, in the case of crossed belts, the construction of 
cone-pulleys is very simple, since it is only necessary to observe 
the directions given above, no matter what the distance between 
the centres of driving and driven pulley may be. 




CONE PULLETS, FIG. 3. 

Case 4. — Open "belt passing over two continuous pulleys. (Fig. 3.) 

For this case equal and similar conoids must be used. Assume 
the largest radius, A F, and the smallest, B D, and calculate, by the 
rule on page 111, the length of belt required for pulleys with the 
given radii, the distance, K L, between their centres being given. 
Then the middle radius, C H, is found by the following rule : 

Subtract twice the distance between centres from the length of 
the belt, and divide the difference by the number 6.2832. 

Having found the middle radius, draw circular arcs through the 
points F H D and Gr I E, thus determining the section of the 
conoid. 

Example. — Suppose that the largest radius is 24 inches, the 



130 



ENGIN^EERING. 



smallest 6 inches, and the distance between centres of conoids 3 
feet. What should be the middle radius ? 

First find the length of belt : 2 diminished by 0.5 equals 1.5. 
This divided by 8 equals 0.5, and the corresponding number in 
table of factors, page 111, is 1.047— (1). 1.047 multiplied by 1.5 
equals 1.571 — (2). 2 added to 0.5 equals 2.5, which multiplied by 
3.1416 equals 7.854 — (3). 3 multiplied by 3 equals 9, which less 
2.25 equals 6.75. 1.5 multiplied by 1.5 equals 2.25. The square 
root of 6.75 is 2.6, which multiplied by 2 equals 5.2— (4). The 
sum of 5.2 and 1.571 and 7.854 equals 14.625, which is the length 
of belt. Then find the middle radius by the preceding rule : 3 
multiplied by 2 equals 6. 14.625 less 6 equals 8.625, which divid- 
ed by 6.2832 equals 1.373 feet, or about 16i inches, middle radius 
required. 



I i 

HHSmBb I 

n 



CONE PULLETS, FIG. 4. 



Case 5. — Opeti belt pamag over two stepped cones that are equal 
and opposite. — (Fig. 4.) — The construction will be evident from 
the figure, it only being necessary to form two continuous conoids, 
as explained above, and divide them into the required number of 
steps. 

Case 6. — Open belt passing over any two stepped cones. — The 
rules for this case, originally demonstrated by J. B. Henek, are 
presented below in a simplified form. First assume the radii of 
one driving-pulley and the corresponding driven pulley, measure 
the distance between their centres, and find the length of belt re- 



ENGINEERING. 131 



quired. Then assume values for the radii of the successive pul- 
leys on the driving-cone, and calculate the values of the corre- 
sponding radii on the driven cone by the following rules : I. Hav- 
ing assumed the value of one radius, it is first necessary to ascer- 
tain whether the one to be calculated is larger or smaller. (1) 
Multiply the assumed radius by the number 8.1416, and increase 
the product by the distance between the centres of the pulleys. 
(2) If the quantity obtained by (1) is greater than half the length 
of the belt, the assumed radius is greater than the one to be de- 
termined. (3) If the quantity obtained by (1) is less than half 
the length of the belt, the assumed radius is less than the one to 
be determined. II. When the assumed radius is the greater of the 
two, to find the other one. The distance between centres and the 
length of belt are supposed to be given. (1) Multiply the as 
sumed radius by the number 6.2832, subtract this product from 
the length of the belt, and divide the remainder by the distance 
between centres. (2) Add the quantity obtained by (1) to the 
number 0.4674, and extract the square root of the sum. (3) 
Subtract the quantity obtained by (2) from the number 1.5708, and 
multiply the difference by the distance between centres. (4) 
Subtract the quantity obtained by (3) from the assumed radius ; 
the remainder will be the required radius. III. When the assumed 
radius is the smaller of the two. to find the other one. (1) Same as 
(1) of preceding rule. (2) Same as (2) of preceding rule. (3) 
Subtract the number 1.5708 from the quantity obtained by (2), and 
multiply the difference by the distance between centres. (4) Add 
the quantity obtained by (3) to the assumed radius ; the sum will 
be the required radius. 

Example. — The first driving-pulley of a stepped cone has a ra- 
dius of 12 inches, and the radius of the corresponding driven 
pulley is 4 inches ; the distance between centres of pulleys is 3 
feet, and there are three other pulleys on the driving-cone, having 
radii of 9, 6, and 3 inches respectively. It is required to find the 
radii of the corresponding pulleys on the driven cone. It will be 
necessary first to calculate the length of belt required, which is 
10.334 feet, or about 10 feet 4 inches. 

Next find whether the pulleys on the driving or driven cone are 
the largest. Half the length of belt is 5.167 feet. For the 9- 
inch pulley, 0.75 multiplied by 3.1416 is 2.356, and adding 3, the 
sum is 5.356, which is greater than 5.167, showing that the 9-inch 
pulley is larger than the pulley to be determined. For the 6 -inch 
pulley: 0.5 multiplied by 3.1416 equals 1.571, and increased by 3 
equals 4571, and as this is less than 5.167, the 6-inch pulley is 
smaller than the pulley to be determined. Of course, then, the 
remaining 3-inch pulley is still smaller than the corresponding 
pulley in the driven cone. 

To find the radius of the pulley corresponding to the one on 
the driving-cone whose radius is 9 inches : (1) 0.75 multiplied by 
6.2832, 4.712. Subtracting 4.712 from 10.334, the remainder is 
5.622 ; 5.622 divided by 3, 1.874. (2) 0.467 added to 1.874, 2.341. 
Square root of 2.341, 1.53. (3) Subtracting 1.53 from 1.571, the 
remainder is 0.041 ; 0.041 multiplied by 3, 0.123. (4) Subtract- 
ing 0.123 from 0.75, the remainder is 0.627 feet, or about 7i 
inches, radius of required pulley. 



132 ENGINEERING. 



Pulley corresponding to driving-pulley whose radius is 6 
inclies : 0.5 multiplied by 6.2882 equals 3.142. This subtracted 
from 10.834 equals 7.192, which divided by 3 equals 2.397— (1). 
Adding 0.467, we have 2.864, the square root ot which is 1.692 
—(2). 1.692 diminished by 1.571 equals 0.121, which multiplied 
by 3 equals 0.363— (3). Adding 0.5 gives 0.863 feet, or about 
lO^Y inches, required radius. 

Pulley corresponding to driving-pulley whose radius is 3 
inches : 0.25 multiplied by 6.2832 equals 1.571. This, subtracted 
from 10.334, equals 8.763. Dividing the last by 3 gives 2.921— 
(1) ; and by adding 0.467 we have 3.388. Of this the square root 
is 1.841— (2). Subtracting 1.571 gives 0.27, which multiplied by 3 
equals 0.81, and adding 0.25 gives 1.06 feet, or about 12i-^ inches, 
required radius. 

The radii of the several pulleys on the two cones then will be : 

Driving-cone .12, 9, 6, 3 inches. 

Driven cone 4, 7i, IOJy* '^^h inches, 

B. 

Pulleys, Set- screws for. — These should be made of cast- steel 
with hollow points ; the ends should then be beveled to an edge 
surrounding the hole, and tempered to a dark straw. When set 
up, these screws cut circular indentations on the shaft, and exert 
an enormous force of resistance. 

Pulleys, Working value of. — Pulleys covered with leather, 
iron pulleys polished, and mahogany pulleys polished, rank for 
working value as 36, 24, and 25 per cent respectively, wood and 
iron uncovered being almost identical. 

Rawhide Boxes for machinery. — A practical machinist says : 
*' I have run a piece of machinery in rawhide boxes for fourteen 
years without oil ; it is good yet, and runs at 4500 per minute. I 
put it in while soft, and let it remain until dry." 

Shafting Accidents, Preventing. — Accidents are common in 
large manufactories through the engagement of some portion of 
a workman's garments with a swiftly rotating shaft. A simple 
way of rendering these casualties impossible is to cover the shaft 
with a loose sleeve along its whole length. The sleeve may be 
of tin or zinc, and made so as to be removable if desired. The 
friction between it and the shaft would be sufficient to cause its 
rotation with the latter, but of course, in event of a fabric be- 
coming wrapped around it, it would quickly stop, and allow of 
the easy extrication of the same. The sleeve should be lined 
with leather both within and at the ends in order to prevent 
noise. The same idea in the shape of loose covers might readily 
be applied to cog-wheels or pulleys. 

Shafting, Lining. — Every one operating long lines of shaft- 
ing should provide an adjusting-rod, as shown in the engraving. 
A may be a rod or a piece of gas-pipe, of sufficient length to 
reach from the shaft, O, to within about 4 feet of the floor ; an 
offset piece, B, is fixed to the top of this rod, which carries a 
right and left hand screw, C ; two jaws, D, travel upon this 
screw, one upon the right and the other upon the left hand 



ENGINEERING. 



133 



lio 



thread, as shown. The screw may be worked by a i-in. wire, E, 
with a crank, F, at its lower end ; if a gas-pipe is used, the wire 
may pass through the pipe, and the lower 
end of the screw, C, enter the top of the 
pipe as a bearing. If the rod. A, is of wood, 
three or four wire staples will suffice as 
guides for the wire, as indicated. A tar- 
get, G, with a clamp-screw, slides upon 
the rod, for the purpose of easy adjustment 
to the sights of the leveling instrument. 

Now it will of course be apparent to 
every one that, whenever several sizes of 
shafting occur in the same line, this ad 
justing- rod will always give the exact 
central distance, O, of the shaft from the 
target ; hence we have only to plant the 
leveling instrument in a position to com- 
mand a view of the target when suspend- 
ed from each of the several bearings of a 
line of shafting", in order to adjust the lev- 
el of a line with the utmost expedition 
and accuracy. An eno^ineer's tripod and 
level is, of course, the best instrument for 
this purpose, but, when this is not at 
hand, an ordinary builder's level may be 
used: .the longer it is, the better. Fix a 
temporary sight at one end of the level ; a 
piece of tin (with a small pin-hole) next 
the eye, and a piece of tin or thin wood 
with a large hole at the farther end, with 
a vertical and a horizontal thread stretch- 
ed across the hole, with their point of 
intersection the same distance above the 
level as the hole in the eye-piece. The 
level may be used upon a level stand or 
table, some five feet from the floor. 

To adjust a line of shafting laterally, 
an adjusting-rod must of course be used 
horizontally in connection with a strong 
line, stretched as taut as possible, at such 
distance from the shafting as to need 
nearly the full length of the rod to reach 
it. The reason for placing the line at 
such a distance from the shaft is to pre 
vent the difference in level between the 
line and the shaft from materially impair- 
ing the truth of the result. If the line is 
very long, it will sag so much that a 
plumb-line suspended from the measuring 
point of the target or rod may be neces- 
sary for perfect accuracy. 

The jaws, D, should be so formed that 
they may be applied to the inside of boxes. Pivot-boxes are 



DEVICE FOR LINING 
SHAFTING. 



134 ENGINEERING. 



now so generally used, however, that this application of the rod 
is not so common. 

Shafts, Sprung. — If a shaft springs in running, the trouble 
lies probably in either a too small diameter of the shaft for its 
weight and velocity, a set of unbalanced pulleys, or an unequal 
strain on either side by the belts. 

Wood, Lubricant for. — A mixture of black-lead and soap. 



ill' 



PEAOTICAL TECHNOLOGY. 



CEMENTS, GLUES, AND MOULDING COMPO- 
SITIONS. 

Casts, To prepare plaster of Paris for. — Immerse the unburnt 
gypsum for 15 minutes in water containing 8 or 10 per cent of 
sulphuric acid, and then calcine it. Prepared in this way it sets 
slowly, but makes excellent casts, which are perfectly white 
instead of the usual grayish tint. 

Casts, Transparent. — Beautiful semi-transparent casts of fancy 
articles may be taken in a compound of 2 parts unbaked gyp- 
sum, 1 part bleached beeswax, and 1 part paraffine. This be- 
comes plastic at 120°, and is quite tough. 

Cements. — Air and loater -tight, for casks and cisterns : Melt- 
ed glue 8 parts, linseed-oil 4 ; boil into a varnish with litharge. 
This hardens in 48 hours. Plumbers' : Black resin 1 part, brick- 
dust 2. Melt together. For leaky boilers : Powdered litharge 2 
parts, fine sand 2, slaked lime 1. Mix with boiled liu seed-oil. 
Apply quickly. Acid-proof : A paste of powdered glass and 
concentrated solution of water-glass. Cutlers' : (1) Pitch 4 parts, 
resin 4, tallow 2, and brick-dust 2. (2) Resin 4, beeswax 1, brick- 
dust 1. (3) Resin 16, hot whiting 1, wax 1. This is used for fas- 
tening blades in handles. For ivory or mother-of-pearl : Isinglass 
1 part, white glue 2, dissolved in 30 parts hot water and evaporated 
to 6 parts. Add gum-mastic tj^q- part, dissolved in ^ part alcohol, 
and add 1 part zinc- white. Shake up and use warm. Jeweler's, for 
uniting all substances : Gum-mastic 5 or 6 bits as large as a pea dis- 
solved in spirits of wine sufficient to render all Uquid. In another 
vessel dissolve the same amount of isinglass in rum enough to 
make 2 ozs. of strong glue, adding 2 small pieces of gum ammo- 
niacum, which must be moved until dissolved. Heat and mix 
the whole. Keep in a closely-corked phial, and put the latter in 
bo":ng water before using. Black, for bottle-corks: Pitch hard- 
ened by the addition of brick-dust and resin. For jet : Use shel- 
lac, warming the edges before applyinor, and smoke the joint to 
make it black. For meerschaum or china : (1) Make a dough of 
garlic, rub on the edaes and bind tightly together. Boil the 
object for half an hour in milk. (2) Use quicklime mixed to a 
thick cream with white of eo^g. Soft, for steam-boilers : Red or 
white lead in oil 4 parts, iron borings 3 parts. Gfasfltters' : Resin 
^ parts, wax 1, Venetian red 3. Coppersmiths' : Boiled linseed- 
oil and red lead made into a putty. This is used to secure joints 
and on washers. For emery on to wood : Equal parts of shellac, 
white resin, and carbolic acid in crystals. Add the acid after the 



136 PRACTICAL TECHNOLOGY. 

others are melted. Iron and emery : Coat the meta. with oil 
and white-lead, and when hard apply the emery mixed with glue. 
French putty, hard and permanent : Linseed-oil 7 parts, brown 
umber 4, boiled for 2 hours, -J- part white- wax stirred in. Re- 
move from fire and thoroughly mix in white-lead 11, and fine 
chalk 5^ parts. India-ruhher : Fill a bottle -j^ full of native 
india-rubber cut into fine shreds. Pour in benzole from coal-tar 
till the bottle is f full. The rubber will swell ; and if the whole 
be shaken every few days, the mixture will become as thick as 
honey. If too thick, add benzole ; if thin, add rubber. This 
dries in a few minutes, and will nnite backs of books, straps, 
etc. , very firmly. Chinese, for fancy articles, wood, glass, etc. : 
Finest pale-orange shellac, broken small, 4 parts, rectified spirit 
3 parts. Keep in a corked bottle in a warm place until dissolved. 
It should be as thick as molasses. Bust joints : (1) Clean iron 
borings 2 parts, flowers of sulphur j^, sal-ammoniac Ve. (2) 
Finely-powdered iron borings 1 part, sal-ammoniac i, flowers of 
sulphur jt. Pound together and keep dry. For use, mix 1 part 
with 20 of pounded iron borings, and mix to a mortar consis- 
tence with water. For making metallic joints sound : (1) Use 
a putty of boiled linseed-oil and red-lead. (2) Use & 
putty of equal parts of white and red lead. For electrical and 
chemical apparatus : Resin 5 parts, wax 1, red ochre 1, plaster of 
Paris \. Melt at moderate heat. For mending stone, or as mas- 
tic for hrick walls : Make a paste of linseed-oil with clean river 
sand 20 parts, litharge 2, quicklime 1. For chucking work in the 
lathe : (1) Black resin 8 parts, yellow wax 1 ; melt together. For 
use, cover the chuck to -^ in. thick, spreading over the surface in 
small pieces, mixing it with \ its bulk of gutta-percha in thin 
slices. Heat an iron to dull red and hold it over the chuck till 
the mixture and gutta-percha are melted and liquid. Stir the 
cement with the iron until it is smoothly mixed. Chuck the 
work, lay on a weight to enforce contact, and let it rest for half 
an hour before using. (2) Burgundy pitch 2 parts, resin 2, yellow 
wax ^, dried wax 2. Melt and mix. (3) Resin 4 parts, melted 
with pitch 1. While boiling add brick-dust until dropping a 
little on stone shows the mixture to be suflGlciently hard. Elastic, 
for leather or india-rubber : Bisulphide of carbon 4 ozs., shred- 
ded india-rubber 1 oz., isinglass 2 drachms, gutta-percha i oz. 
Dissolve, coat the parts, dry, then heat the layer to melting, 
place and press the parts together. Water -tight, for wooden vessels : 
Lime, clay, and oxide of iron, mixed, kept in a close vessel and 
compounded with water for use. For leather, straps, etc. : Gut- 
ta-percha dissolved in bisulphide of carbon. Keep tightly corked 
and cool. It should be of the consistence of molasses. For mar- 
ble, or for attaching glass to metal : Plaster of Paris soaked in 
a saturated solution of alum and baked hard. Grind to powder 
and mix with water for use. Can be colored to imitate any 
marble, and takes a fine polish. Impervious, for corks, etc. : 
Zinc-wliite rubbed up with copal varnish. Give two coats so as 
to fill all the pores, and finish with varnish alone. For cracks in 
wood : (1) Slaked lime 1 part, rye meal 2, and linseed-oil 2. (2) 
Use a paste of sawdust and prepared chalk with glue 1 part, 
dissolved in water 16. (3) Oil-varnish thickened with eqiial 



PRACTICAL TECHNOLOC^. I37 



parts of litharge, chalk, and white and red lead. For wood arid 
glass or metals : (1) Resin and calcined plaster, the former melted, 
made into a paste. Add boiled oil to consistence of honey. (2) 
Dissolved glue and wood-ashes to consistence of varnish. * Fire- 
proof and water-proof : Pulverized zinc- white, sifted peroxide 
of manganese, equal parts. Make into a paste with soluble 
glass. 2^0 mend iron pots and pans : Partially melt 2 parts sul- 
phur, and add 1 part fine black-lead. Mix well, pour on stone, 
cool, and break in pieces. Use like solder with an iron. London 
cement, for glass, wood, china, etc.: Boil a piece of cheese three 
times in water, eacli time allowing the water to evaporate. Mix 
the paste left with quicklime. For aquaria : (1) For fresh water 
aquaria : Take \ gill gold-size, 2 gills red-lead, \^ gills litharge, 
and suflficient silver sand for a thick paste. This sets in about 2 
days. (2). For fresh or salt water : Take ^ gill powdered resin, 
1 gill dry white sand, 1 gill litharge, 1 gill plaster of Paris. 
Sift ; and for use mix with boiled linseed-oil to which a little 
dryer has been added. Mix 15 hours before using, and allow 2 or 
3 hours to dry. For petroleum lamps, impervious to the oil : Re- 
sin 3 parts, boiled with water 5 and caustic soda 1. Then mix 
with half its weight of plaster of Paris. This sets in f hour. 
Roman : Green copperas 3^ lbs., slaked lime 1 bushel, fine gravel 
sand 1 bushel. Dissolve the copperas in hot water, and mix all 
to proper consistence. Keep stirred. Glass to glass, for sign- 
letters, etc. : Melt in a water-bath liquefied glue 5 parts, copal 
varnish 15, drying-oil 5, oil of turpentine 2, turpentine 3. Add 
slaked lime 10. Hydraulic : Oxide of iron 1 part, powdered 
clay 3, and boiled oil to a stiff paste. Stone : Sand 20 parts, 
litharge 2, quicklime 1, mixed with linseed-oil. Leather and 
cloth, for uniting parts of boots and shoes, seams, etc. : Gutta- 
percha 16 parts, india-rubber 4, pitch 2, shellac 1, oil 2. Mix and 
use hot. Mahogany : Shellac melted and colored. Colorless, for 
paper : Add cold water to rice-flour, mix, bring to proper con- 
sistence with boiling water, and boil one minute. Water-proof, 
for cistern stones : (1) Whiting 100 parts, resin 68, sulphur 18^, 
tar 9. Melt together. (2) Sand 100 parts, quicklime 28, bone 
ashes 14, mixed with water. Transparent : India-rubber 75 
parts, chloroform 60. Mix, and add mastic 15. Cloth to iron : 
Soak the cloth in a dilute solution of galls, squeezing out the 
superfluous moisture, and applying the cloth, still damp, to the 
surface of the iron, which has been previously heated and coated 
with strong glue. The cloth should be kept firmly pressed upon 
the iron until the glue has dried. For cracks in stoms : Finely- 
pulverized iron (procured at a druggist's) made into a thick paste 
with water-glass. The hotter the fire, the more the cement 
melts and combines, and the more completely does the crack be- 
come closed. For china, glass, etc. : Diamond cement, for glass 
or china, is nothing more than isinglass boiled in water to the 
consistence of cream, with a small portion of rectified spirit 
added. It must be warmed when used. 2. White-lead rubbed 
up with oil. Articles mended with this must stand for a month. 
For corks of henzine-hottles : A paste of concentrated glycerine 
(commonest kind) and litharge. This soon hardens, and is insolu- 
ble in benzine or any of the light hydro- carbon oils. For caustic 



138 1>RACTICAL TECHl^OLOaY. 

lye tanks : The tanks may be formed of plates of heavy-spar, 
the joints being cemented together by a mixture of 1 part finely 
divided india-rubber dissolved in 2 parts turpentine oil, with 4 
parts powdered heavy-spar added. Colored : Soluble glass of 33*^ 
B. is to be thoroughly stirred and mixed with fine chalk and the 
coloring matter well incorporated. In the course of six or eight 
hours a hard cement will set. The following are the coloring 
materials : 1. Black : Well-sifted sulphide of antimony. This 
can be polished with agate to a metallic lustre. 2. Gray-black : 
Fine iron-dust. 3. Gray : Zinc-dust. This has a brilliant lus 
tre, and may be used for mending zinc casting*s. 4. Bright green : 
Carbonate of copper. 5. Dark green : Sesquioxide of chromium. 
6. Blue: Thenard's blue. 7. Yellow: Cadmium. 8. Bright red : 
Cinnabar. 9. Violet red : Carmine. 10. Pure white : Fine 
chalk as above. 

Cement, Portland, To test. — Three tests are used : (1) Resist- 
ance to tensile force. (2) Specific gravity. (3) W ater test. The 
first is by making a specimen briquette in a mould with a trans- 
verse section of 2.25 square inches, the specimen being held ver- 
tically in clips, which is placed under the short arm of a steel- 
balance, and broken. A test of 500 lbs. has been used on an area 
of 2.25 square inches after 7 days' immersion in water. The sec- 
ond method is by finding the weight in pounds of the struck 
bushel. The water test is useful when the others can not be ap- 
plied. It consists of gauging a small quantity of the dry powder 
with water, and immediately immersing it in water. If the 
sharper edges crack or break away after a short time, the cement 
is too hot or fresh, or is inferior in quality. The weight of good 
Portland cement ranges from 100 lbs. to 130 lbs. per bushel, equal 
to from 80 lbs. to 102 lbs. per cubic foot. The lighter kinds set 
more rapidly than the heavier, bat are weaker. The specific gra- 
vity should be of 110 lbs. to a bushel. 

Glued Joints, Strength of. — The absolute strength of a well- 
glued joint is given as follows in pounds per square inch : 





Across the grain. 


With the grain. 


Beech, 


2133 


1095 


Elm, 


1436 


1124 


Oak, 


1735 


568 


Whitewood, 


1493 


841 


Maple, 


1422 


896 



It is customary to use from ^ to -fo of the above values to cal- 
culate the resistances which surfaces joined with glue can perma- 
nently be submitted to with safety. 

Glue, Fire-proof. — A handful of quicklime mixed in 4 ozs. of 
linseed-oil and boiled to a good thickness makes, when spread on 
plates and hardened, a glue which can be used in the ordinary 
way, but which will resist fire. 

Glue, Liquid.— Dissolve the glue in an equal amount of strong 
hot vinegar, adding \ alcohol and a little alum. Will keep in- 
definitely. 

Glues, Marine. — (1) Pure india-rubber 1 pt., dissolved by heat 



PKACTICAL TECHNOLOGY. 139 

in naphtha ; when melted, add shellac, 2 pts. (2) Glue, 12 pts., 
water to dissolve, and yellow resin, 3 pts. Melt, add turpentine, 
4 pts., and mix. Portable, for draughtsmen : Glue 5 ozs., sugar 
2 ozs., water 8 ozs. Melt in water-bath, cast in moulds, and dis- 
solve for use in warm water. For lank-notes : Fine glue or 
gelatine, 1 lb., dissolved in water, and the water evaporated until 
nearly expelled. Add ^ lb. brown sugar, and pour in moulds. For 
gutta-percha: Common black pitch 2 pts., gutta-percha 1 pt. 
Mould into shape. Elastic : Dissolve glue in a water-bath, evapo- 
rate to a thick fluid, and add an equal weight of glycerine. Cool 
on a slab. Liquid : (1) White glue 16 ozs., dry white-lead 4 
ozs., soft water 2 pints, alcohol 4 ozs. Stir and bottle while hot. 
(2) Glue 3 pts. softened in 8 parts water. Add ^ pt. muriatic acid 
and I pt. sulphate of zinc. Heat to 176° Falir. for 12 hours. Al- 
low the compound to settle. Heat and moisture-proof ; Linseed- 
oil 4 ozs., 1 handful of quicklime ; boil to good thickness, and 
cool. It will become very hard, but is as easily dissolved as com- 
mon glue. Water-proof simple : Common glue 1 lb. boiled in 
2 qts. skimmed milk. 

Glue, Test for goodness of. — Assuming that that is the best 
glue which will take up most water, take 50 grains of the speci- 
men and dissolve it in 3 ozs. water in a water-bath. When dis- 
solved, set it by for 12 hours to gelatinize, and then take an 
ounce chip-box, place it on the surface of the gelatine, and put 
shot into the box until it sinks down to a mark on the outside. It 
will be found that the stronger the glue, the more shot it will 
take to sink the box down so that the mark shall be level with 
the surface of the gelatine. In a trial with very fine glue, 50 
grains of glue dissolved and gelatinized with 3 ozs. of water, 
supported to the mark on the box 6 ozs. of shot, at a temperature 
of 58^ Fahr. On trying the same experiment with best Russian 
isinglass, 9 ozs. of shot were supported, the temperature being 
the same. This test is of course intended as a comparative one 
between two kinds of glue, or between any kind taken as a stand- 
ard and another compared with it. The placing of the mark is 
arbitrary. 

Glue, To bleach. — Soak in moderately strong acetic acid for 
two days, drain, place on a sieve, and wash well with cold water. 
Dry on a warm plate. 

Moulding Architectural Ornaments. — A good composition 
for this purpose is made of chalk, glue, and paper-paste. 

Moulding Composition.— Five parts of sifted whiting mixed 
with a solution of 1 part glue, together with a little Venice turpen- 
tine to obviate the brittleness, makes a good plastic material, which 
may be kneaded into figures or any desired shape. It should be 
kept warm while being worked. It becomes as hard as stone 
when dry. 

Paste, To mould figures in. — Take the crumb of a new-drawn 
white loaf, mould in a mass until the whole becomes as close as 
wax and very pliable. Then heat and roll with a rolling-pin. 
Mould it to the required shape, and dry in a stove. 



140 PRACTICAL TECHNOLOGY. 

Photographic Pkints, To varnish. — Heat a piece of glass, and 
rub a little wax over it with a bit of cotton- wool. Pour water 
over the plate, and press the picture down upon it with a piece 
of filtering-paper. When dry, the picture is removed, and will 
be found to possess a brilliant surface. 

Picture-Frames, Composition for.— (1.) To make composi- 
tion ornaments for picture-frames : Boil 7 lbs. best glue in 3^ 
pints water, melt 8 lbs. white resin in 3 pints raw linseed-oil ; 
when the ingredients are well boiled, put them into a large ves- 
sel and simmer them for half an hour, stirring the mixture and 
taking care that it does not boil over. When this is done, pour 
the mixture into a large quantity of whiting, previously rolled 
and sifted very fine, mix it to the consistence of dough, and it is 
ready for use. (2) Dissolve 1 lb. glue in 1 gallon water ; in another 
kettle boil together 2 lbs. resin, 1 gill Venice turpentine, and 1 pint 
linseed-oil ; mix together in one kettle, and continue to boil and 
stir them together till the water has evaporated from the other in- 
gredients ; then add finely-pulverized whiting till the mass is 
brought to the consistence of soft putty. This composition will 
be hard when cold ; but being warmed, it may be moulded to any 
shape by carved stamps or prints, and the moulded figures will 
soon become dry and hard, and will retain their shape and form 
permanently. Frames of either material are well suited for gild- 
ing. 

Plaster Casts, To toughen. — Immerse in a hot solution of 
glue long enough for the mass to be well saturated. They will 
bear a nail driven in without cracking. 

Plaster Models^ Mending. — Sandarac varnish is the best ma- 
terial. Saturate the broken surfaces thoroughly, press them well 
together, and allow them to dry. 

Plaster Moulds. — Glycerine is said to be a good coating for 
the interior, but practical plaster moulders still use, as of old, a 
mixture of lard and oil. 



METAL-WORKING HINTS AND RECIPES. 

Alloy for filling defects in small castings. — Lead 9 parts, 
antimony 2, bismuth 1. This expands on cooling. 

Alloy of Copper, which will attach itself to glass, metal, or 
porcelain. — 20 to 30 parts finely blended copper (made by reduc- 
tion of oxide of copper with hydrogen or precipitation from solu- 
tion of its sulphate with zinc) are made into a paste with oil of 
vitriol. To this add 70 parts mercury and triturate well ; then 
wash out the acid with boiling water and allow the compound to 
cool. In 10 or 12 hours, it becomes sufficiently hard to receive a 
brilliant polish and to scratch the surface of tin or gold. When 
heated it becomes plastic, but does not contract on cooling. 

Alloy, '' Oroide." — This is made of pure copper 100 parts, tin 
17 parts, magnesia 6 parts, sal-ammoniac 3i parts, quicklime 1^ 



PRACTICAL TECH]vrOLOGY. 141 

parts, tartar of commerce 9 parts. The copper is first melted, then 
the magnesia, sal-ammoniac, lime, and tartar in powder are added 
little by little and briskly stirred for half an hour. The tin is 
lastly mixed in grains until all is fused. The crucible is covered, 
and the fusion maintained for 35 minutes, when the dross is 
skimmed off and the alloy is ready for use. 

Alloys, To extract silver from old. — Dissolve in nitric acid and 
precipitate the chloride of silver with a solution of common salt. 
The silver is reduced to a pure state by mixing the chloride with 
an equal weight of bicarbonate of soda and smelting in a common 
sand crucible. 

Aluminum Silyer.— The following alloy is distinguished by 
its beautiful color, and takes a high polish : Copper 70, nickel 
23, aluminum 7, total 100. 

Babbitt Metal. — There are a aarge number of recipes for this 
alloy, but the following gives an excellent composition for gene- 
ral use : Tin 50 parts, antimony 5 parts, copper 1 part. 

Bell, Cracked, To repair. — A cracked bell which gives a jar- 
ring sound may be improved by sawing or filing the ruptured 
edges so that they are not brought together by the vibration of 
the blow. 

Boiler-tubes, Iron, To preserve. — A coating of red-lead and 

boiled linseed-oil, applied to iron boiler-tubes, acts as a great 
preservative. 

Brass, Black stain for. — Arsenious acid 2 parts, hydrochloric 
acid 4, sulphuric acid 1, water 80. 

Brass Scrap, To utilize. — The best way is to melt it m with 
new brass, putting it in with the zinc after the copper is melted. 

Brass, To blacken. — Mix 4 parts hydrochloric acid and 1 part 
arsenic (by weight) ; put on bright, dry, and lacquer. 

Brass, To clean. — Rub bichromate of potash fine, pour over 
it about twice the bulk of sulphuric acid, and mix this with an 
equal quantity of water. The dirtiest brass is cleaned by this 
in a trice. Wash the metal immediately after in plenty water ; 
wipe, rub dry, and polish with powdered rottenstone. 

Brass, Vert de Bronze on. To produce. — Dissolve 2 ozs. ni- 
trate of iron and 2 ozs. hyposulphite of soda in 1 pint water. 
Immerse the articles till they are of the required tint, as almost 
any shade from brown to red can be obtained ; then wash well 
with water, dry, and brush. One part per chloride of iron and 
2 parts water mixed together, and the brass immersed in the 
liquid, gives a pale or deep olive-green, according to the time of 
immersion. If nitric acid is saturated with copper, and the brass 
dipped in the liquid and then heated, the article assumes a dark- 
green color. 

Bronze for gongs and cymbals. — This is made with 20 per 
cent of tin, and is hammered into shape while at a red heat ; it 
is then tough and malleable, but is very brittle when cold. 

Bronze for small castings. — Fuse together 95 parts of copper 
and 36 parts of tin. 



142 PRACTICAL TECHNOLOGY. 

Bkonze, Green. — The bluisli-green bronze used for ornamental 
articles is made of any metal, first covered with a varnish made 
of ground tin or bronze powder rubbed up with honey in gum- 
water. Then wash with a mixture composed of sal-ammoniac 
^ oz., common salt | oz., and 1 oz. spirit of hartshorn in 1 pint 
vinegar. After applying tlie mixture, leave for a day or two in 
tlie sun, and then, if necessary, add a second coat. This is a 
good way to renovate old gas-fixtures. 

Bronze, Japanese. — A curious bronze is produced in Japan, 
which, when made in thin plates, resembles slate, and is covered 
with designs in silver. It contains, in addition to copper, from 4 
to 5 per cent of tin, and on an average 10 per cent of lead. The 
combination is easily moulded into thin plates. These are var- 
nished, and through the covering the designs are scratched with 
a burin. The plate is then plunged in a silver-bath, when the 
silver is deposited on the unprotected portions. Lastly, it is 
placed in a muffle-furnace, when the copper blackens and the 
silver remains bright. 

Bronzing Hardware. — Brown bronze dip, for coating hat- 
hooks and similar small hardware articles, is made of iron scales 
1 lb., arsenic 1 oz., muriatic acid 1 lb., zinc, solid, 10 ozs. The 
zinc should be kept in only when the bath is used. The castings 
must be perfectly free from sand and grease. 

Case-hardening, to be quickly performed, is done by the use 
of prussiate of potash. This is powdered and spread upon the 
surface of the iron to be hardened, after the iron is heated to a 
bright red. It almost instantly fluxes and flows over the surface ; 
and when the- iron is cooled to a dull red, it is plunged in cold 
water. Some prefer a mixture of prussiate of potash 3 parts, 
sal-ammoniac 1 part ; or prussiate 1 part, sal-ammoniac 2 parts, 
and finely-powdered bone-dust, (unburned) 2 parts. The appli- 
cation is the same in each case. Proper case-hardening, when a 
deep coating of steel is desired, is done by packing the article in 
an iron box with horn, hoof, bone-dust, shreds of leather or raw 
hide, or either of these, and heating to a red heat for from 1 to 
3 hours, then plunging the box into water. 

Chain, Strength of. — To ascertain the strength of short-linked 
chains: (1) Multiply the square of the diameter (reckoned in six- 
teenths of an inch) by .035 ; the product will be the weight the 
chain will support in tons. (2) The square of the diameter in 
eighths of an inch = weight of chain in lbs. per fathom. The 
square of the diameter in eighths -^ 2 = breaking weight in tons. 
Thus for a chain made of f iron, the weight = 3^ = 9 lbs. per 

fathom, and its breaking weight would be -|i = 4| tons. The ut 
most load put upon it should not exceed 1^ tons, the safe con- 
stant load being 18 to 20 cwt. 

Coloring Metals. — Take hyposulphite of soda 4 ozs., dis- 
solved in 1^ pints of water ; add a solution of 1 oz. acetate of 
lead in same quantity of water. Articles to be colored are placed 
in the mixture, which is then gradually heated to boiling. The 
effect of the solution is to make iron resemble blue steel ; zinc 
becomes bronze, and copper or brass becomes successively yel- 
lowish-red, scarlet, deep blue, bluish-white, and finally white 



PEACTICAL TECHNOLOGY. 143 

witli a tinge of rose. The solution has no effect on lead or tin. 
By replacing the acetate of lead in the solution with sulphate of 
copper, brass becomes of a fine rosy tint, then green, and finally 
of an iridescent brown color. Zinc does not cover in this solution ; 
but if boiled in a solution containing both lead and copper, it be- 
comes covered with a black crust, which may be improved by a 
thin coating of wax. 

Columns, Strength of hollow.— The hollow cylinder is the 
strongest form of section under compressive force. The experi- 
ments by which this was proved were conducted upon hollow 
tapering columns of cast-iron, upon cross-sections, as used in the 
connecting-rods of steam-engines, and upon forms in which the 
metal was cast in the shape of the letter H. All these forms 
proved considerably weaker than the hollow cylinder of equal 
weight of metal. As the relative merits of these forms of cast- 
ing metal are of constant use, we append their proportionate 
strengths: Hollow cylindrical pillar, 100; H- shaped pillar, 75; 
+ -shaped pillar, 44. The examples were all of the same weight 
and length, with rounded ends. General Morin's rule for the 
thickness of cast-iron pillars may be relied upon, as it is based 
upon the founder's experience of the minimum thickness. 
Height, feet, 7 to 10, 10 to 13, 13 to 20, 20 to 27.; minimum 
thickness, inch, 0.5 0.6 0.8 1.0 

Another rule is to make the thickness in no case less than ^ 
of the diameter. Cellular or tubular girders exemplify to a still 
greater degree the value of hollow construction. 

Copper and Brass, Coating, with zinc. — Dip the articles into a 
boiling concentrated solution of sal-ammoniac containing finely- 
divided zinc. 

Copper- WELDING. — A good welding mixture is composed of 
phosphate of soda 358 parts, boracic acid 124 parts. 

Crucibles. — The best crucibles are composed of the following 
compositions, which are of two kinds — namely, with and without 
plumbago. 3 parts by measure of the Stourbridge best crucible 
clay, 2 parts cement, consisting of old used-up fire-bricks, and 1 
part hard coke. These ingredients must be ground and sifted 
through a \ in. mesh sieve ; the sieve must not be finer, other- 
wise the pot will crack. This composition must be mixed with 
sufficient clean cold water, trodden with the bare foot to the con- 
sistency of stiff dough and allowed to stand for 3 or 4 days, well 
covered with damp cloths, to admit of its sweating and the parti- 
cles of clay becoming thoroughly matured. It is then ready for 
use, and must be blocked by hand on a machine. Owing to the 
coarseness of this composition, the pot can not well be thrown on 
the potter's wheel ; and in no instance can it be made by press- 
ing. The crucible must not be burnt in a kiln, but merely highly 
and thoroughly dried before being placed in the furnace for use. 
For brass and copper melting, it will stand one good hard day's 
work ; but care must be taken to replace the pot again in the 
furnace after the metal has been poured. If the pot be not al- 
lowed to go cold, it will last for several days. It will, w^ith the 
greatest safety, stand one melting of wrought-iron. The cost, 
when made on the steel manufacturer's own premises, is about 



144 PRACTICAL TECHNOLOGY. 

forty cents per pot, each pot holding from 100 to 120 pounds of 
metal. Good Hessian crucibles are composed of 2 parts of the 
best German crucible clay and 5 parts pure fine quartz sand. 
This composition must be sifted through a ^ in. mesh sieve ; it is 
then tempered and trodden with the bare foot, as before de- 
scribed. When ready for use, it is pressed into different sizes of 
crucibles, which, when thoroughly dry, are placed in the kiln or 
furnace and burnt hard. 

Another coinposition : 2 parts best Stourbridge crucible clay, 
3 parts cement ; sift through a -^-in. sieve ; temper as before de- 
scribed and block by hand on the machine. When thoroughly 
dry, it is placed in the kiln and burnt hard. These crucibles are 
principally used for melting gold and silver, and also for dry 
analysis. The best and most perfect fire-clay for crucible mak- 
ing is nearly always found in the pavement of coal. Some of the 
Pittsburg fire-clays, and those found to exist in the pavements 
of some of the Pennsylvania coal-mines, are excellent fire-clays. 
But the various compositions can not be described, as they are as 
numerous as the different kinds of clay. The Birmingham soft 
tough pot consists of 2 parts of the best Stourbridge crucible 
clay, 3 parts plumbago, and 1 part cement, consisting of old used- 
up crucibles ground and sifted through a \ in. mesh sieve. 

Another composition : 4 parts of the best Stourbridge crucible 
clay, 3 parts plumbago, 2 parts hard coke, and 1 part cement, 
consisting of old pots ground and sifted as before. Where old 
pots can not be had, the above composition must be burnt hard, 
ground, and sifted. The scales or chippings of the insides of 
gas-retorts are far superior to the best common hard coke. But 
where scales and chippings can not be had, hard coke is the best 
substitute. All the ingredients of this composition must be sifted 
through a \ in. sieve (but not finer), tempered, and made as be- 
fore described. When thoroughly dry, it is placed in the kiln 
and annealed, but not burnt hard. This composition makes a 
pot (for melting the hardest metal) which can not be melted at 
any pitch of heat, nor can it be cracked with the most sudden heat- 
ing and cooling. It is regularly known to stand 14 and 16 melt- 
ings of iron — even wrought-iron. Any steel manufacturer can 
make the pot on his own premises at a cost of $1.20 or there- 
abouts, the pot holding from 100 to 120 lbs. of metal. 

Etching upon Steel. — Warm the steel, and rub on a coatino^ 
of white- wax or hard tallow. When hard, mark the device 
through the wax with a sharp-pointed tool ; apply nitric acid, 
and allow it to stand for a few minutes ; then wash off the acid 
thoroughly with water, heat the steel, and rub off the wax with a 
rag. The device will be found etched on the steel. 

Gold and Silver, Test for. — A good test for gold or silver is 
a piece of lunar caustic, fixed with a pointed stick of wood. 
Slightly wet the metal to be tested, and rub it gently with the 
caustic. If gold or silver, the mark will be faint ; but if an in- 
ferior metal, it will be quite black. 

Gun-Barkels, To bronze.— Clean thoroughly, and apply (by 
means of a rag) nitric or sulphuric acid diluted with its volume 
of water. 



PRACTICAL TECHl^OLOGY. 145 

Hardening Pickle. — Spring-water made into a brine strong 
enough to float an egg, then boiled to precipitate the lime, and 
allowed to cool. 

Iron Articles, Brightening. — When taken from the forge or 
rolls, the articles are placed in dilute sulphuric acid (1 to 20) for 
an hour ; they are then washed clean in water, dried with saw- 
dust, dipped for a second or so in nitrous acid, washed and dried 
as before, and finally rubbed clean. 

Iron Rings, Welding, without scaling. — Take iron filings 
1000 parts, borax 500 parts, resinous oil of any kind 50 parts, 
sal-ammoniac 75 parts. Pulverize completely and mix ; heat the 
rings to a cherry red, powder the parts with the mixture, and 
join them together. 

Iron, Simple fire-plating for. — By rubbing the surface of iron 
or other metals with soda amalgam, and then pouring over it a 
concentrated solution of chloride of gold, the gold is taken up by 
the amalgamated surface, and it is only necessary to drive off the 
mercury with the heat of a large lamp to obtain a fine gilded sur- 
face that will bear polishing. By writing or drawing a design 
on the iron, the drawing will be re-produced in pure gold. Silver 
and platinum salts are said to act in a similar manner to the 
gold. 

Iron, To gild cast. — The cheapest way is to use bronze or 
mosaic gold. The castings are first to be heated hotter than the 
hand can bear, but not so hot as to burn the varnish, and coated 
with mosaic gold mixed with a small quantity of alcohol varnisli. 
If the iron is polished, it must be heated previously and rubbed 
over with a rag dipped in vinegar. 

Lead, Determining presence of, in tin vessels. — The metal to be 
tested is first touched with nitric acid and then heated, when the 
acid evaporates. If lead be contained, stannic acid and nitrate of 
lead remain. Iodide of potassium is then applied, forming yel- 
low iodide of lead ; while the stannic acid is white. The yellow 
stain, therefore, indicates lead, the white, tin. 

Jewelry, To restore the lustre of. — Take 1 oz. cyanide potas- 
sium and dissolve in 3 gills water. Attach the article to be 
cleansed to a wire hook, immerse and shake in the solution for a 
second or two, and remove and wash in clean water, then in warm 
water and soap. Rinse again, dip in spirits of wine, and dry in 
boxwood sawdust. If the solution is kept, put it in a tightly- 
corked bottle, and label POISON conspicuously. One caution is 
necessary : Do not bend over the solution so as to inhale the 
odor, nor dip the fingers in it ; if one of the articles drops from 
the hook, better empty the solution into another vessel. 

Metal Surfaces, To protect, from moisture.— Inclose them 
in tight compartments containing lumps of quicklime. 

Minerals and Metals, Hardness and tenacity of. — In mine- 
ralogy, in which science the hardness is an important characte- 
ristic, ten bodies are usually taken as points of comparison — the 
softest being termed 1 and the hardest 10. These are: 1, talc ; 
2, gypsum ; 3, carbonate of lime ; 4, fluor-spar ; 5, phosphate of 
lime ; 6, felspar ; 7, quartz ; 8, topaz ; 9, corundum ; 10, dia- 



146 PRACTICAL TECHNOLOGY. 

niond. Hence, when scientific works speak of the hardness of a 
body being 6, 8, 4, etc. , reference is made to the relative hard- 
ness expressed by the list above given. 

The tenacity of "metals is estimated by the resistance which 
wires of the same diameter experience when passed at equal tem- 
perature through the same hole of a draw-bench. The following 
table gives the relative tenacity of various metals and alloys : 
Steel already drawn, 100 ; iron already drawn, 88 ; brass already 
drawn, 77 ; gold at 0.875, annealed, 73 ; steel annealed, 65 ; cop- 
per already drawn, 68 ; silver at 0.750, annealed, 58 ; silver at 
0.875, 54 ; brass annealed, 46 ; iron annealed, 42; platinam an- 
nealed, 38 ; copper annealed, 38 ; fine gold annealed, 37 ; fine 
silver annealed, 37 ; zinc, 34 ; tin, 11 ; lead, 4. 

Platinum-Bronze. — This is made of nickel IQO parts, tin 
10, platinum 1. It is entirely unoxidizable, and especially 
adapted for cooking-utensils. 

Quicksilver, Coating: iron with. — Clean the iron first with hy- 
drochloric acid, then immerse it in a dilute solution of sulphate 
of copper mixed with a little hydrochloric acid, by means of 
which it becomes covered with a slightly-adherent layer of cop- 
per. It is then to be brought into a very diluted solution of mer- 
curial sublimate mixed with a few drops of hydrochloric acid. 
The article will become covered with a layer of mercury, which 
can not be removed even by rubbing. This is good as a protec- 
tion from rust. 

Sadirons, Finishing. — See that your buff- wheels are well- 
balanced after they are covered. Let the wheel be covered with 
thick leather before covering with emery. Get as good a surface 
on the article as you can from a wheel covered with No. 70 emery. 
Mix flour of emery with melted beeswax, and stir in till it is 
thick. When the mass is cool, rub it on a newly-covered wheel 
with No. 80 emery. Then set the wheel running, and hold on a 
flint to smooth it until the surface is sufiiciently fine to suit. 

Silver Ornaments, Imitation. — Ordinary plaster models are 
covered with a thin coat of mica powder, which perfectly re- 
places the ordinary metallic substances. The mica plates are 
first cleaned and bleached by fire, boiled in hydrochloric acid, and 
washed and dried. The material is then finely powdered, sifted, 
and mingled with collodion, which serves as a vehicle for apply- 
ing the compound with a paint-brush. The objects thus prepar- 
ed can be washed in water, and are not liable to be injured by 
sulphuretted acids or dust. The collodion adheres perfectly to 
glass, porcelain, wood, metal, or papier mache. 

Silver, Producing satin finish on, by sand-blast. — The follow- 
ing is the method adopted at a laro^e silver-plating establishment : 
Air is compressed by the driving-engine of the works into an or- 
dinary reservoir, and thence distributed through pipes which ex- 
tend along the front of the workmen's tables ; and above the lat- 
ter is a sand receptacle, V-shaped, from which a stream of sand 
falls, and is met by a downward blast from the pipe, which cur- 
rent drives the material in a stream through a small hole in the 
table, beneath which a receptacle to receive the sand is placed. 
The workman, whose fingers are covered with rubber to protect 



PRACTICAL TECHNOLOGY. 147 

them, holds the article in the jet and under the table, watching 
it through a pane of glass let into the top of the latter. The 
operation is necessarily very rapid, as the article has only to be 
turned so that the blast strikes the required portions, when the 
work is completed. The exposure to the jet, even for an instant, 
wo aid cut through the Britannia, upon which the plating is 
afterward deposited. By the interposition of rubber screens of 
suitable shape, against which the sand has no abrading effect, any 
fancy patterns or letters are easily imprinted on the surface, the 
latter, of course, being satin-finished, while the spaces protected 
by the screens are afterward burnished. 

Silver, Restoring color to. — This is adapted to treating silver 
filagree ornaments, rendering them dead white. The process has 
long been a trade secret. If any pewter is found in the articles, 
it should not be attempted. Pound together charcoal 3 parts, 
and of nitre 1 ; add sufficient water to form a paste. With a 
camel's-hair brush give the article a thin coat of the mixture, put 
it in a small annealing-pan, and submit it to the fire until it be- 
comes red-hot ; then withdraw it from the fire, let it stand a mi- 
nute, and tarn it out into a weak solution of sulphuric acid (1 part 
acid, 10 parts water) in the boiling-pan. Boil, pour off the acid, 
rinse ; wash with warm water and soap, using a soft brush ; dip 
in spirits of wine, and dry in boxwood sawdust. If any spots 
should still remain on the work, anneal it without the mixture, 
boil out and wash as before. Burnish the parts intended to be 
bright. Do not use the common American saltpetre. The Eng- 
lish nitre, although it costs more, is really less expensive, as a 
smaller quantity goes further and does the work more effectual- 
ly. Purchase at the wholesale druggists. 

Silver, To regain, from broken black-lead crucibles. — Pulve- 
rize the crucible and digest it in nitric acid for several hours. 
Decant off the clear liquid, and add to it muriatic acid until no 
further precipitate forms. Allow to settle, and again decant the 
clear liquid, wash the precipitate several times with clean water, 
dry, and fuse in a small crucible with a quantity of carbonate of 
soda. 

Slag, Utilization of. Prussian method. — The high furnaces 
are provided with a continual overflow for the slag, which runs 
through a narrow gutter formed in the sand into a shallow pit, 
through which a small stream of water is kept running. By this 
chilling process the slag assumes the form of a fine gravel. An 
endless chain at once lifts the slag out of the pit and loads it upon 
cars. By grinding this material fine in a cement-mill, it is form- 
ed into an excellent sharp building-sand ; the great bulk of it, 
however, is used, without further reducing its grain, for making 
bricks. 

For this purpose it is mixed with one half of its bulk of mor- 
tar in a trough in which three shafts provided with long blades 
are revolving. It is then shoveled into the brick-machines, each 
of which turns out about twenty-five bricks a minute. These bricks 
are piled up in the open air for drying, and are ready for use after 
about six weeks. They continue to harden on exposure to the 
air, and are said to possess greater strength than ordinary burnt 



148 PRACTICAL TECHNOLOGY. 

bricks. They are extensively used for all kinds of buildings, 
their light-gray color producing a very pleasing effect, and the 
roughness of their surface fitting them particularly well for re- 
taining a coating of mortar. They can not be used, however, for 
foundation walls, as by the absorption of moisture their cohesive- 
ness is impaired. 

The most interesting process is the following : As a thin stream 
of the fluid slag, falling from a narrow gutter, passes the nozzle 
of the steam-pipe, a jet of steam is blown through it, and by this 
simple process it is solidified in the form of most delicate fibres, 
resembling asbestos or spun glass ; and it falls to the ground like 
a loose mass of grayish wool. This material is an excellent 
non-conductor of heat, and is used for covering steam-pipes, boil- 
ers, etc. The sole expenditure in its manufacture is that of the 
steam, the exact amount of which could not be ascertained. 
The material is sold for about $5 per cwt. The steam-pipe is 
about li inches in diameter, and the nozzle is simply a pipe, flat- 
tened and then curved into a semicircular form, in order to give 
the most advantageous shape to the steam-jet. The steam used 
has a pressure of about 50 lbs. per square inch. 

Soldering Liquid. — Into hydrochloric acid place as much 
scrap-zinc as it will dissolve, still leaving a sponge of zinc. Use 
the mixture for soldering brass-work. To solder cast or wrought 
iron, add sal-ammoniac ; and for sheet-tin work, omit the sal-am- 
moniac. 

Solder, Jewelers'. — Melt 1 part lead, add 2 parts tin, and 
throw in a small bit of resin as a flux. This is strong, easily 
flowing, and white. In soldering fine work, wet the parts to be 
joined with muriatic acid in which as much zinc has been dissolv- 
ed as the acid will take up. It is cleaner than the old method of 
using Venice turpentine or resin. 

Solder, Silver. — Put into a clean crucible, silver 2 parts, clean 
brass 1 part, with a small piece of borax. Melt and pour into in- 
gots. Solder made from coin, as it frequently is, often meets 
with difficulty around the joints, requiring the use of the file to 
remove it, while the addition of any of the inferior metals to the 
solder causes it to eat into the article joined by it. 

Steel and Iron, To clean, from temporary and slight rust. — 
Cocoanut husks are better than waste and turpentine. 

Steel, Chrome. — This metal is not only one third stronger 
than any other steel, but can be produced at a small cost, from 
the fact that when worn out, as in a steel -headed rail, it has a 
market value, as it can be made over again, which is not the case 
with Bessemer or any other cast-steel. It will also weld without 
borax or flux, and when burnt can be redeemed on the next heat. 

Steel, Polished, To bronze. — To 1 pint methylated spirits 
add 4 ozs. gum-shellac and i oz. gum-benzoin ; put the bottle in 
a warm place, shaking it occasionally. When dissolved and set- 
tled, decant the clear liquid and keep it for fine work. Strain the 
residue through a fine cloth. Take ^ lb. powdered bronze green, 
varying to suit the taste with lampblack, red ochre, or yellow 
ochre. Take as much varnish and bronze-powder as required, 
and lay it on the article, which must be thoroughly clean and 



PRACTICAL TECHNOLOGY. 149 

slightly warm. Add anotlier coat if necessary. Touch up with 
gold-powder according to taste, and varnish over all. 

Steel, Protecting, from rust. — Paraffine is the best material 
for polished steel or iron. 

Steel Rails, Cutting. — Remarkable results have been obtain- 
ed with a disk made from a rail-saw and rotated at 3000 revolu- 
tions per minute. As the disk was 9.6 feet in diameter, the velo- 
city of its circumference was in the neighborhood of 86,400 feet 
per minute. Steel rails were cut with astonishing rapidity, and 
even melted. Millions of sparks were thrown off, but no heating 
of the disk could be detected after the cutting. 

Tin, Crystallization of. — A platinum capsule is covered with an 
outer coating of paraffine or wax, leaving the bottom only unco- 
vered. This capsule is set upon a plate of amalgamated zinc in 
a porcelain capsule. The platinum is then filled completely full 
of a dilute and not too acid solution of chloride of tin, while the 
porcelain is filled with water acidulated with ^ of hydrochloric 
acid, so that its surface comes in contact with the surface of the 
liquid in the platinum. A feeble electric current is set up, which 
reduces the salt of tin. The crystals formed after a few days are 
well developed.. They are washed with water and dried quickly. 

Tin, Removing, from copper vessels. — Immerse the articles in 
a solution of blue vitriol. 

Tin, Removing, from plates without acid. — Boil the scrap-tin 
with soda lye in presence of litharge. 

Welding Powders for iron and steel. — (1) Iron filings 1000 
parts, borax 500, balsam copaiva, or other resinous oil, 50, sal- 
ammoniac 75. Mix together, heat, and pulverize. Weld at cher- 
ry-red. (2) Borax 15 parts, sal-ammoniac 2, cyanide of potas- 
sium 2. These constituents are dissolved in water, and the wa- 
ter itself afterward evaporated at a low temperature. 

Zinc, Black color for. — Clean the surface with sand and sul- 
phuric acid, and immerse for an instant in a solution of sulphate 
of nickel and ammonia 4 parts, in water 40 parts, acidulated with 
sulphuric acid 1 part. Wash and dry. This takes a bronze 
color on burnishing. 

Zinc Labels, Ink for writing on. — (1) Verdigris 1 oz., sal-am- 
moniac 1 oz., lampblack ^ oz., water ^ pint ; mix well in a mor- 
tar, and shake before using. Write with a quill. (2) One drachm 
chloride of platinum dissolved in ^ pint water. 

Zinc, Painting. — Use a mordant of chloride of copper 1 part, 
nitrate of copper 1, sal-ammoniac 1, dissolved in water 64. Add 
hydrochloric acid (commercial) 1. This brushed over the zinc 
sheets gives them a deep black color, turning grayish after dry- 
ing, in from 12 to 24 hours. A coat of oil-color will adhere to 
this surface and withstand weather excellently. 

Zinc- White, To restore.— This may be done by ignition in an 
earthen crucible. 



150 



PRACTICAL TECHNOLOGY. 



SIMPLE INSTRUMENTS AND THEIR USES. 

Balance, Simple spring. — A is a deal stand 12 by 3 inches ; 
B is a hard-wood block firmly attached to A ; C is a spring ; 
D is an index-pillar ; E is a scale-holder ; F is a small bent pin 
to hold the spring steady while changing the scale-pan. The 




SIMPLE BALANCE. 



spring C should be very fine steel wire, bent over so as to form 
a loop near the index for E to hook into. The index is a slip of 
card set out with a fine pen. The scale-pan is of thin letter- 
paper, circular, and folded like a filter-paper, as indicated by the 
dotted line. With this minute fractions of a grain can be re- 
cognized. 

Barometer, To make a cheap. — Obtain a straight fine glass 
tube, about 33 inches long, and with as clean an interior as possi- 
ble, sealed at one end, and having an even uniform bore of about 
2t lines diameter. The mercury to be used should be perfectly 
pure and free from all air and moisture. This latter requisite 
may be assured by heating the mercury in a porcelain dish to 
nearly the boiling-point, previous to using it. The tube is then 
held securely, with the open end uppermost, and carefully filled 
with the liquid metal. The open end of the tube is then securely 
covered with the finger, the tube inverted, and the end covered 
by the finger plunged below the surface of a little mercury placed 
in a small vessel to receive it. The finger is then removed, when 
the mercury in the tube will immediately fall to a level of about 
30 inches above the surface of that in the small reservoir below. 
In order to attach the scale correctly, it will be necessary to com- 
pare the indications with those of some good instrument. 

Baroscope, To make a. — Take any bottle ; pour colored water 
into it, about ^ of the quantity the bottle will hold ; insert in it a 
glass tube, from 3 to 4 feet long, and passing air-tight through 
the stopper, which must also be air-tight. Let a paper index, 
divided according to any scale of division, say into inches and 
fractions of an inch, be glued to the glass tube. Blow into the 



PRACTICAL TECHNOLOGY. 



151 



glass tube so as to cause the water to ascend the tube a few inches, 
bay 10 inches, and the instrument is constructed. The bottle 
must be placed in another vessel, and protected by sawdust, or 
some other material, from the influence of changes in the tempe- 
rature of the atmosphere. This very sensitive instrument records 
faithfully any change in the density of the external air, and the 
approach of a storm will infallibly be indicated by a sudden rise 
of the water in the glass tube. 

Camera, Wonder, How to make a. — A wonder camera is a 
sort of magic lantern, so contrived as to enable one to use opaque 
objects for projection upon the screen, in stead of glass transparen- 
cies. For example, if a photograLer wishes to show his customer 
how an enlargement from a carte will look, he simply has to put 
the carte in the wonder camera, and " throw it up." Many en- 
largement-scales may be made in this way. It consists of a 
wooden box, with a top made of tin or sheet-iron ; the chimney 
is made of the same material. The lens is the same as used upon 
a camera for making photographs. At the back of the box (as 
will be seen by reference to the elevation and plan. Figs. 2 and 8) 
are two doors placed upon hinges. 

When the box is in use, the door e is kept closed. The other 
door consists of two parts placed at right angles to one another ; 





Fig. 1. 



Fig. 2. 



A WO]?fBEIl CAMERA. 



the object of this is to fill the opening in the door e while the 
pictures are being attached to c ; when g is swung into position 
opposite, the lens, placed at h d, is carried to one side. If stereo- 
scopic views are to be shown, a slit maybe cut at e, through 
which they may be inserted with- 
out opening the box. The door e 
should be cut off a little at the 
bottom, so as to admit air. The 
li^ht is placed at h, as nearly oppo- 
site the picture as possible. It 
should be a strong light ; an ar- 
gand burner is the best. At the 
back of the light is a piece of tin, 
bent into the form of a reflector. 
Tlie light coming from h strikes c, and is reflected through 
the lens upon the screen. The plan of the box is represent- 
ed with the top removed. No dimensions are given, as they 
will depend upon the focal distance of the lens and height of 




Fig. 3. 



152 PRACTICAL TECHNOLOGY. 

the light. Care must be used to have the distance from the 
lens to c when closed equal to the focal distance. 
Electrical Machine, A simple. — A B, in the annexed en- 




A SIMPLE ELECTRICAL MACHINE. 

p^raving, is a glass tube fixed at one end. in a wooden handle. 
The rubber, with its flap, D, carries a little Leyden jar, the 
end of which is visible at F. This jar is coated inside and 
out with a resinous insulating compound, and the metallic lining 
of the inside of the jar is in contact with the brass collecting- 
ring, E. The handle being held in one hand and the rubber in 
the other, when the tube is rubbed the little ring and jar rapidly 
collect electricity. A ^ inch spark and smart shock may be readily 
obtained from this apparatus, the length of the spark depending 
upon the amount of rubbing each time before the jar is dis- 
charged. When it is not desired to take the shock through the 
human body, the jar may be discharged by means of the metallic 
cord, H. 

Electrical Orrery, to accompany the above machine. — This 
is represented below. It is balanced on a pivot at F. The 





ELECTRICAL ORRERY. 

light hollow brass ball. A, represents the sun, and pith balls, B 
and D, the earth and moon, rotating about the pivot E. The 
metallic points projecting from B and D (in opposite directions, 
of course) cause these to rotate round each other ; but the lever- 
age of the point D being, from its position, greater than the 
leverage of B, it sets the long arm of the orrery in rotation upon 
the pivot F. 

Galvanometer, To make a simple. — Take an ordinary pocket- 
compass and wind 100 feet of No. 18 insulated copper wire 
around it. 

Kaleidoscope, To make a. — Take two strips of glass, 8 or 10 
in. long, 1 to \\ in. broad at one end and about \ as broad at the 
other. Blacken one side of each with black varnish. Put two 
smooth straight edges together, and form a hinge by gluing a 
strip of cloth over the two edges. Make the angle between the 



PRACTICAL TECHNOLOGY. 153 

strips of glass an aliquot part of 180°, as 20*^, 30^, or 45^. Cover 
the open side of the triangular prism with black velvet. Place 
in a tin or pasteboard tube so that the angle of the smaller end of 
prism is nearly in the centre. Cover top of tube with clear glass, 
and cover this with paper, except a small hole in centre. In bot- 
tom of tube, form a cell by placing two pieces of glass ^ in. apart 
(the lower one of ground glass). In this cell place fragments of 
broken colored glass, beads, etc. They must be capable of free 
movement in the cell when the tube is turned in the hand. 

Leyden Jar, To make a cheap. — Line a thin glass candy-jar 
inside and outside with tin-foil, such as is used to wrap chew- 
ing-tobacco in. Stick the foil, on with mucilage, varnish, or 
flour paste. A still cheaper plan is simply to fill a glass jar nearly 
full of water, and place it within another vessel of water, so that 
the water, both outside and inside, shall be on the same level. 

Magic-Lantern Slides, Painting. Four methods, — (1) Use 
transparent colors, like Prussian blue, gamboge, and carmine. 
These will give the three primary colors, and by their mixture, 
the other tints. Apply with a brush, and a transparent drying 
varnish, like dammar varnish. Allow one coat to dry before ap- 
plying a second. Considerable aid can be derived from stippling, 
the color being strengthened, where necessary, by applying it 
Avith the point of a fine brush. The colors must not be used too 
thin. (2) Flow the glass plate with albumen, after the manner 
of photographers, and paint with aniline colors. This process 
gives great softness and brilliancy to the pictures, but they are 
apt to fade. (Jj) Paint with water-colors, and then flow the entire 
surface with Canada balsam, covering the painted side with a 
glass plate. (4) Use water-colors, but mix them with turpentine 
instead of water, and work rapidly. 

Meridian, To find the. — Mr. G^eorge W. Blunt says : " Take a 
piece of board, or any similar material, and describe on it a num- 
ber of concentric circles. Place this in the sun ; over the centre 
hang a plummet. Observe the shortest shadow from the plum- 
met ; the sun will then be on the meridian ; draw a line to the 
centre of the circle, and that will be the true meridian-line. This 
will do to mark the apparent time, or to correct the compass for 
variation." 

Mirrors, Globe, To make. — Melt together 1 oz. clean lead and 
1 oz. of fine tin in a clean iron ladle ; then immediately add 1 oz. 
bismuth. Skim off the dross, remove the ladle from the fire, and 
before it sets add 10 ozs. quicksilver ; now stir the whole care- 
fully together, taking care not to breathe over it, as the fumes of 
mercury are very pernicious. Pour this through an earthen pipe 
into the glass globe, which turn repeatedly around. 

Pipes, Determining proportions of. — The instrument consists 
simply of a piece of wood shaped like a set- square, as shown in 
Fig. 1, or a diagram of the same form drawn on paper, and di- 
vided out along the two edges, which are at right angles to each 
other, the divisions being taken to represent inches, feet, or yards, 
etc., according to the kind of work for which the instrument is 
used. Suppose that two pipes, A and B, Fig. 2, respectively 5 in. 



154 



PRACTICAL TECHNOLOGY. 



and 4^ in. in diameter, deliver into a third pipe, D, and it be re- 
quired to find the proper diameter for the latter pipe. Then from 
5 on the scale of one of the divided edges to 4^ on the other, 




APPARATUS FOR DETERMINING THE DIAMETER OF PIPES. 

draw a line, as shown dotted in Fig. 1, and the length of this 
line, measured with the same scale as that to which the edges are 
divided, will be the diameter of pipe required ; in this case, 6f 
in. On the other hand, if a pipe, D, 6f in. in diameter, be deliver- 
ed into a pipe. A, 5 in. in diameter, and it was required to know 
what other size of pipe, B, could also be supplied, all that would be 
necessary would be to take the division point 5 on one edge as a 
centre, and, with 6 J in. as a radius, describe an arc cutting the 
other divided edge. The point at which the latter edge was cut 
by this arc would show the diameter of pipe required. 

Rifle-Telescope, To make a. — Object-glass should be half an 
in. in diameter, focus 24 in., or as long as convenient. Eye-piece 
may be a single lens of low power with cross spider-lines fixed in 
its focus. The target will then appear inverted. The lenses are 
inclosed in a brass tube with a hinge or ball- joint at the breech or 
eye-piece end, and slides at the muzzle, to depress the object-glass 
for increased elevation. The two points of attachment to the bar- 
rel are the same as for ordinary fore-and-leaf sights. 

Telescope, To make a cheap. — A correspondent says : "I se- 



PRACTICAL TECHKOLOGY. 155 

lected a meniscus 1 in. in diameter and of 48-in. focus. Tliis was 
for my object-glass. I bad already in my possession a two-lensed 
double-convex jeweler's eye-glass ; one of tbese lenses was used 
for tbe eye-piece, its focal lengtb being a trifle over 1 in. Tbe 
tube was made of pine-wood. A piece of straigbt, evenly-grained 
one-in. pine board, 2 in. wide and 8 feet long, was cut in the mid- 
dle, and the two pieces, after making a tapering semicircular 
groove in each, well glued together. This done, the next thing 
was to give it a round, tapering form, 2 in. in diameter at one end, 
and a trifle over an inch at the other. This was done with a com- 
mon carpenter's plane. I now had a tube 4 feet long, with a ta- 
pering hole through its length, and 1^ in. in diameter at its larg- 
est end. Two wooden cells for the lenses were then turned in a 
lathe, and were made to go on to the tube, as does the cover of a 
wooden pill-box, A round hole, the size of the lens, was made 
in each, the meniscus being contracted to f in., and the eye-glass 
to i in. diameter. The piece carrying the eye-glass was made so 
as to slide some distance on the tube, for adjustment to distinct 
vision. The tube was painted and varnished, and mounted equa- 
torially ; and it proved to be a good instrument, showinor Jupiter's 
moons, their movements and eclipses, handsomely, the ring of 
Saturn, the horned appearance of Venus, the mountains and cra- 
ters on the moon, the spots on the sun, etc. Several of the nebu- 
lae were also visible, especially those mfAndromeda, Orion, Her- 
culefi^ and Sagittarius. The whole need not cost over two dollars, 
beside the time in making, provided one is a mechanic. 

** The meniscus (concave on one side and convex on the other) 
is the proper form for a single-lens object-glass, and a plano-con- 
vex lens makes the best form for the eye-piece. Care must be 
taken to so set the lenses in their cells that their foci will meet 
centrally. When this is the case, the lenses are said to be well 
centred, and in that way we get rid of most of the prismatic 
color. Another point that wants attention is the mounting. Ab- 
solute steadiness is required for close observation. I used to put 
mine upon a post set firmly in the ground. The equatorial ar- 
rangement for mounting is described in nearly every work on 
telescopes." 

Thermometers, Hard-rubber. — This instrument has been made 
by riveting the rubber to a thin strip of steel, about a foot in 
length and J in. in width. The bottom of this was held fast, 
while the top was free to move, and so to indicate the temperature 
on a graduated arc. This one, now in use, has a range from zero 
to 90^ Fahr., and is as sensitive as the common mercurial thermo- 
meter. It is well adapted for the ordinary range of the atmo- 
sphere, but is not suitable for indicating high degrees of heat, 
as the rubber softens at about 200^ Fahr. Another thermometer 
was made by perforating a thin strip of steel, at intervals of an 
inch, and placing upon it a strip of rubber compound when in a 
plastic state. This was coiled, with an intermediate strip of me- 
tal, which forced the rubber through the holes. It was then vul- 
canized in the usual manner ; and when cold, the intermediate 
strip was withdrawn, leaving an open space between the coils. 
This saved the trouble of riveting, and gave to the rubber an un- 
broken and smooth, surface. The coil is held fast at the centre, 



156 PRACTICAL TECHNOLOGY. 



and the outer end is left free to move. Another thermometer was 
made of glass and hard rubber, the latter In the form of an arc, 
being riveted at both of its ends to a glass plate, which formed 
the chord. 

Thermometers. — To change Fahrenheit degrees into Centi- 

grade : C. =:— ^ ^ . Centigrade into Fahrenheit : F. = -' -|- 32. 

9R 

Reaumur into Fahrenheit : ¥.= *4- 32. Fahrenheit into 

4 ' 

Reaumur : R. =i— - ' ^ > Reaumur into Centigrade : C.=^ — • 

4C. 
Centigrade into Reaumur : R.=— - 

5 



RECIPES FOR THE PREPARATION OF WOOD. 

Dyeing Woods. — All light woods may be died by immersion. 
A fine crimson is made a^ follows : Take 1 lb. ground Brazil, boil 
in 3 quarts of water, add ^ oz. cochineal, and boil another half 
hour ; may be improved by washing the wood previously with ^ 
oz. saffron to 1 quart water. The wood should be pear wood or 
sycamore. Purple satin : 1 lb. logwood chips, soak in 3 quarts of 
water, boil well an hour ; add 4 ozs. pearlash, 2 ozs. powdered 
indigo. Black may be produced by copperas and nutgalls, or 
by japanning with two coats of black japan, after which varnish 
or polish, or use size and lampblack previous to laying on ja- 
pan. A blue stain : 1 lb. oil of vitriol put in a glass bottle with 4 
ozs. indigo ; lay on the same as black. A fine green : 3 pints of 
the strongest vinegar, 4 ozs. best powdered verdigris (poison), ^ 
oz. sap-green, ^ oz. indigo. A bright yellow may be stained with 
aloe ; the whole may be varnished or polished. 

Ebony, Artificial. — Treat sea-weed for 2 hours in dilute sul- 
phuric acid. Of the charcoal thus obtained take 16 parts ; dry, and 
grind it. Add liquid glue 10 parts, gutta-percba 5, india-rub- 
ber 2J, the last two dissolved in naphtha. Then add coal-tar 10, 
pulverized sulphur 5, pulverized alum 2, powdered resin 5, and 
heat the mixture to 300° Falir. This when hard will take a pol- 
ish equal to ebony, and is the same in color and hardness. 

Oak, To color orange-yellow. — Rub the wood with a mixture 
of tallow 3 ozs., wax f oz., and turpentine 1 pint, mixed by heat- 
ing together and stirring. Apply in a warm room until a dull 
polish is acquired. Then coat, after an hour, with thin polish, and 
repeat until the desired depth and brilliancy of tone is obtained. 

Screws, Wooden, To season. — Bore a hole longitudinally 
through the centre of the screw ; it will not be apt to crack so 
badly in seasoning, because then the air can get to the centre of 
the wood, the sap escapes therefrom, the centre of the wood con- 



PRACTICAL TECHNOLOGY. 157 



tracts, and the strain on the outside is lessened. Of course, the 
larger the hole, the better for the seasoning process ; but it should 
not, and need not, be large enough to materially weaken the screw. 
If, in addition, you can boil the screw in water^ the job will be 
bettered ; if boiled in oil, it will be complete. 

Veneers, Artificial, To make. — Soak the wood for 24 hours, 
and boil for ^ hour in a 10 per cent solution of caustic soda. Then 
wash out the alkali, when the wood will be elastic, leather-like, 
and ready to absorb the desired color. After immersion in the 
color-bath, dry between sheets of papor under sufficient pressure 
to preserve the shape. 

Veneers, Steaming. — Blocks of wood intended for veneers 
may be steamed in a solution of borax and ammonia. They will 
then become soft and easy to cut, and, beside, will retain their 
flexibility for a long time. 

Wood, A liquid. — Sawdust can be converted into a liquid 
wood, and afterward into a solid, flexible, and almost indestruc- 
tible mass, which, when incorporated with animal matter, rolled, 
and dried, can be used for the most delicate impressions, as well 
as for the formation of solid and durable articles, in the following 
manner : Immerse the dust of any kind of wood in diluted sul- 
phuric acid, sufficiently strong to affect the fibres, for some days ; 
the finer parts are then passed through a* sieve, well stirred, and 
allowed to settle. Drain the liquid from the sediment, and mix 
the latter with a proportionate quantity of animal offal, similar 
to that used for glue. Roll the mass, pack it in moulds, and al- 
low it to dry. 

Wooden Labels, Preservation of. — Thoroughly soak the pieces 
of wood in a strong solution of sulphate of iron ; then lay them, 
after they are dry, in lime-water. This causes the formation of 
sulphate of lime, a very insoluble salt, in the wood. The rapid 
destruction of the labels by the weather is thus prevented. Bast, 
mats, twine, and other substances used in tying or covering up 
trees and plants, when treated in the same manner are similarly 
preserved. Wooden labels, thus treated, have been constantly ex- 
posed to the weather during two years without being affected 
thereby. 

Wooden Taps, Preserving, for Casks. — The articles should be 
plunged in paraffine, heated to about 248° Fahr. until no air-bub- 
bles rise to the surface of the melted material. They are then al- 
lowed to cool, and the paraffine is removed from the surface, when 
nearly congealed, by thorough rubbing. Taps thus treated will 
never split or become impregnated with the liquid, and may be 
used in casks containing alcoholic liquors. 

Wood, Brown stain for. — Paint the wood over with a solution 
made by boiling 1 pint catechu (cutch or gambler) with 30 pints 
water and a little soda. Dry, and then paint over with a solution 
of bichromate of potash 1 pint, water 30 pints. By a little dif 
ference in the mode of treatment, and by varying the strength 
of the solutions, various shades of color may be given to these 
materials. The colors will be permanent, and will tend to pre- 
serve the wood. 



158 PRACTICAL TECHNOLOGY. 

Wood, Preserving. — This process is valuable for railway-sleep- 
ers. Steam the timber, and inject a solution of silicate of soda 
for 8 hours. Then soak the wood for the same period in lime- 
water. (Dr. Feuchtwanger's process.) 

Wood, Preservative preparation for. — Mix 40 parts chalk, 50 
resin, 4 linseed-oil, melting them together in an iron pot ; then 
add 1 part of native oxide of copper, and afterward 1 part of 
sulphuric acid. Apply with a brush. When dry, this varnish 
is as hard as stone. 

Wood, To ebonize. — Collect lampblack from a lamp or candle on 
a piece of slate. Scrape off the deposit, mix with French polish, 
and apply to the object in the ordinary way. 

Wood, To fire-proof. — Paint twice over with a hot saturated 
solution of 1 part green vitriol and 3 parts alum. After drying, 
paint again with a weak solution of green vitriol in which pipe- 
clay has been mixed to the consistence of paint. 



THE PREPARATION AND PRESERVATION OF 
NATURAL-HISTORY SPECIMENS. 

Anatomical Specimens, Preserving. — Glycerine will preserve 
the natural colors of marine animals kept immersed in it. 

Birds, Stuffing. — The following tools are required (see Fig. 1). 
— First, there is the scalpel. This can be purchased for a small 
sum from any maker of surgeon's instruments. The blade is 
short and very sharp, while the handle (not jointed) is long 
enough to allow of a firm grasp. From the same maker, a 
couple of pairs of surgeon's scissors should also be obtained, one 
quite small and sharp-pointed, the other of medium size ; also 
two or three sprinof forceps of various dimensions. A small pair 
of pliers for clipping wire is required, some spools of cotton 
(Nos. 10, 30, and 100), a quantity of excelsior and tow, some cot- 
ton batting, a little prepared glue, a number of pieces of wire 
about fifteen inches long, and straight (size No. 20 or there- 
abouts), a box of dry oatmeal, and some arsenical soap. This 
last can generally be obtained of druggists, or, if not, can be 
made of carbonate of potash 3 ounces, white arsenic, white soap, 
and air-slaked lime, 1 ounce each, and powdered camphor, -^^ 
of an ounce. This is combined into a thick paste with water, 
and applied as below described, with a small paint-brush. It 
should be marked as poison, and kept scrupulously out of the 
reach of children or pet animals. 

If the bird has been shot, immediately afterward all the holes 
made in its body, as well as the mouth, should be plugged with 
cotton, in order to prevent the escape of blood or liquids. Opera- 
tions should not be begun for twenty-four hours, so that the body 
may have ample time to stiffen and the blood to coagulate. It is 



PKACTICAL TECHNOLOGY. 



159 



well during this period to inclose tlie bird, head downward, in a 
cone of paper, so that the feathers will be held smooth. 

The first process is skinning. In commencing, the left hand is 
used to part the feathers, exposing the skin from the apex of the 
breast-bone to the tail. With the scalpel held like a pen, a free 
incision is made between these points, care beinof taken to divide 
the skin only, without cutting into the flesh. The skin is then 
pressed apart, and oatmeal dusted into the cut, in order to absorb 
any fluids which may escape. Careful lifting of the skin clear 
of the flesh follows, until the leg is reached, when the scalpel is 
again used to disarticulate the thigh- joints. The bone of each 
thigh is then exposed for its whole length, by pushing back the 
skin, and the meat removed, when the bone is replaced, and the 
other thigh treated in similar manner. 




PIG. 1.— TAXLDBRMICAL IMPLEMENTS. 

The skin is next detached, to the wings, which are cut from 
the body at the joint next the same, and the bones scraped clear 
of meat. Then the neck is divided, so that the skin, with the 
head attached, can be peeled from the entire body clear to the 
root of the tail. The last is bent toward the back with the left 
hand, the finger and thumb keeping down the detached parts of 
the skin on each side of the vent. A deep cut is then made 
across the latter until the back -bone, near the oil-gland at the 
root of the tail, is exposed. Sever the back -bone at the joint. 
This detaches the body, which may be removed and thrown 
aside, while the root of the tail, with the oil-gland, is left. Great 
care is needed in this operation, as, if not enough bone be left at 



160 



PRACTICAL TECHKOLOGY. 



its root, the tail will come out ; but all fleshy matter should be 
neatly dissected away. 

The neck need not be split or in any wise cut. The skin is 
merely pulled over the flesh, as a glove is removed from the 
finger, until the skull is exposed and appears as in the sketch, 
Fig. 2. With the point of the knife, remove the ears ; and on 
reaching the eyes, carefully separate the lids from the eyeballs, 
cutting neither. It requires very delicate and slow work at this 
point, so as not to injure the eyelids. Then scrape out the eye 
cavities, and cut away the flesh of the neck, removing at the 
same time a small portion of the base of the skull. Through 
the cavity thus made extract the tongue and brains, and after 
cleaning away all fleshy matter, paint the eye orbits with arseni- 




FIG. 2.— MODE OF ATTACmNG THE FALSE BODY. 

cal soap, and stuff them tightly with cotton. Care should be 
taken not to detach the skin from the bill, as it is necessary to 
leave the skull in place. Finally, fill the interior of the skull 
with tow (never with cotton), after coating internally with the 
prepared soap. 

The skinning operation being now completed, the stuffing is 
next proceeded with. To prepare for this, the bird, before being 
skinned, should have been measured, first as to its girth about 
the body, and second as to its length from root of tail to top of 
skull, following the shape of the form. From these data an arti- 
ficial body of the right dimensions is constructed and inserted as 
follows : On a piece of straight wire, equal in length to the last 
measurement above mentioned, a bunch of excelsior is secured 



l»RACTiCAL tech:^ology. 



161 



by repeated winding with stout thread. This bundle, which is 
represented in our Fig. 2, is moulded to a shape resembling that 
of the bird's body, and its girth is regulated by the similar 
measurement already obtained from the bird itself. As will be 
seen, it is attached at the end of the wire, the long protruding 
portion of which serves as a foundation for the neck. The ex- 
tremity of the wire is clipped by the pliers to a sharp point, and 
then forced diagonally upward through the skull, on top of 
which it is clinched flat. Cotton batting is then wound about the 
wire between skull and body, until suflBicient thickness is obtain- 
ed to fill the skin of the neck. The position of the various parts 
at this point is represented in Fig. 2. Painting the inside of the 
skin with arsenical soap follows, and then the skin is drawn back 
so as to envelop the false body, and a needle and thread are 
thrust through the nostrils to make a loop for convenience in 
handlinor. 




FIG. 6. — STUFFING THE LEGS. 



The finest pair of forceps is employed to pull the eyelid skin 
into place, to arrange the feathers, and to pull up the cotton in 
the orbits so as to stuff the cavities out plumply. More cotton is 
next pushed down the throat until the same is entirely filled. 
Two pieces of wire — quite stout for large bird — are then sharp- 
ened at one extremity. Taking the wire in one hand and guid- 
ing it with the other, the operator shoves it into the leg, from 
the ball of the foot up alongside the thigh bone, the skin being 
turned back for the purpose. Cotton is then wound about both 
wire and bone, in order to fill the thigh out naturally, and the 
same process is repeated for the other side. The ends of the 
wire below are left protruding in order to support the bird on a 
perch, if such be desired. The upper ends are pushed clean 
through the artificial body, from below up, and clinched on the 



162 



PR ACTIO AT. TECHNOLOGY. 



upper side. This secures the leors, which are afterward bent in 
natural position (Fig. 3). The bird can now be set up — that is, 
the wires stretching out below the claws can be wound about a 
perch or pushed through holes in a board and clinched on the 
under side. In the latter case, it will be necessary to spread the 
claws and fasten them with pins. For small birds, the cut in 
the breast need not be sewn up ; a chicken or larger fowl will 
require a few stitches to hold the edges together. If the tail 
feathers are to be spread, a wire is thrust across the body and 
through each feather, holding all in the proper position. The 
wings are then gathered closely into the body, and two wires. 




riG. 4. — THE BIRD PREPARED FOR DRYINO. 



one from each side, are pushed in diagonally from up, down, and 
through the skin of the second joint (Fig. 4). The wings are 
thus held, and the wires, as well as that through the tail, are left 
protruding for an inch or more. A touch of glue within the eye- 
lids prepares the latter for the eyes. These must be purchased 
from taxidermists, but for small birds common black beads will 
answer. If plain glass beads can be obtained, by the aid of a 
little paint the student can easily imitate the eye of a chicken. 
After the eyes are inserted, a sharp needle is used to pull the 
lids around them and into place. 

The operator must now, with a fine pair of forceps, carefully 



PKACTICAL TEeHJS^OLOGY. 163 

adjust the feathers, smoothing them down with a large camers- 
hair brush. This done, thread must be wound over the body 
very loosely, beginning at the head, and continuing until all the 
feathers are securely bound. The bird is then left to dry for a 
day or two, when the thread is removed, the ends of wire cut off 
close to the body, and the work is complete. 

Entomological Specimens, To preserve, from insect ravages. 
— Place crystals of carbolic acid throughout the cabinets, and the 
evaporation of the crystals will keep them thoroughly saturated 
with carbolic acid vapors, which will kill all living insects therein. 

Fish, To mount and preserve. — It is impossible to preserve 
the iridescent tints of the living specimens ; but before proceed- 
ing to the operation of skinning, it may be stated that the 
scales, as well as their color, may be preserved to a certain de- 
gree by applying tissue-paper to them, which, from the natural 
glutinous matter which covers the scales, will adhere firmly ; 
this being allowed to remain until the skin has dried, may 
easily be removed by moistening with a damp cloth. All small 
fish should be mounted in section, while the larger varieties may 
be preserved entire. Supposing the fish to be of such a size as 
to be mounted in section, first it is necessary that it be as fresh 
as possible, as the scales will become detached if decay set in. 
Place the fish on one side, and cover the side uppermost with 
tissue-paper, as above stated ; also extend the fins by means of 
the same, and allow them to remain a few moments until fixed 
and dry. Having provided yourself with a damp cloth, spread it 
smoothly upon the table, and place the fish upon it, papered side 
down. With the dissecting scissors, cut the skin along an oval 
line, following the contour of the body, but a little below the ex- 
treme dorsal edge and a little above the ventral one, and remove 
the skin included within this line. The remaining skin must 
now be detached from the flesh, beginning at the head and 
separating it downward toward the tail. The spine must be 
severed close to the head, and also at the tail, and the entire body 
removed. All the flesh having been taken from the skin, and the 
eyes removed, the inside must be wiped out and the preservative 
(arsenical soap) applied. The skin should now be filled with 
tow, very evenly placed. When filled, it should be laid, with 
the open side down, upon a board of proper dimensions, and 
fastened to it by small tacks, beginning at the head and fastening 
the edges downward toward the tail. It should then be set aside 
to dry. The paper is, after drying, removed, and eyes of wood 
(painted to the proper colors, and not varnished) are inserted 
with a little putty. Finally the skin should receive a coat of 
colorless varnish, when the specimen is ready for the cabinet. 

Sea- Weed, Preserving specimens of. — The best time to col- 
lect is when the tide has just commenced to flow, after the low- 
est ebb, as the sea -weeds are then floated in, in good condition. 
All specimens should be either red, green, purple, black, or 
olive ; no others are worth preservation. 

Mounting is done by immersing a piece of paper just below 
the surface of the water, and supporting it by the left hand ; 
the weed is then placed on the paper and kept in its place by the 



164 PRACTICAL TECHNOLOGY. 

left thumb, while the right hand is employed in spreading out 
the branches with a bone knitting-needle or a camel's-hair pen- 
cil. If the branches are too numerous, which will be readily 
ascertained by lifting the specimen out of the water for a mo- 
ment, pruning should be freely resorted to, by cutting off erect 
and alternate branches, by means of a sharp-pointed pair of scis- 
sors, close to their junction with the main stem. When the 
specimen is laid out, the paper should be raised gradually in a 
slightly sloping direction, care being taken to prevent the 
branches from running together. The delicate species are much 
improved in appearance by reimmersing their extremities before 
entirely withdrawing them from the water. The papers should 
then be laid flat upon coarse bibulous paper, only long enough to 
absorb superfluous moisture. If placed in an oblique direction, 
the branches are liable to run together. They should be then 
removed and placed upon a sheet of thick white blotting-paper, 
and a piece of washed and pressed calico placed over each speci- 
men, and then another layer of thin blotting-paper above the 
calico. Several of these layers are pressed in the ordinary way, 
light pressure only being used at first. The papers, but not the 
calico, may be removed in six hours, and afterward changed 
every 24 hours until dry.* If the calico be not washed, it fre- 
quently adheres to the algae, and if the calico be wrinkled it pro- 
duces corresponding marks on the paper. The most convenient 
sizes of paper to use are those made by cutting a sheet of paper, 
of demy size, into 16, 12, or 4 equal pieces. Ordinary drawing- 
paper answers the purpose very well. For the herbarium, each 
species should be mounted on a separate sheet of demy or cart- 
ridge size. Toned paper shows oif the specimens well, *a neutral 
tint answering best for the olive, pink for the red, and green for 
the green series. 

Skins of Small Animals, Dyeing.— The green hull of the 
European walnut is turned to account in Europe for dyeing furs 
black, and the hull of our black walnut could probably be simi- 
larly employed. The walnut hull is crushed and the juice 
squeezed out from the pulp, with the addition of a little water. 
A small quantity of lime is added, and the dye is ready for use. 
The color is extremely difficult of extraction, and attaches itself 
very readily to any kind of hair, and it is used extensively as a 
hair-dye. 

Stuffing small Quadrupeds. — Begin by making a longi- 
tudinal incision between the hind legs, extending quite back to 
the vent, the hair having been carefully parted so that it may 
not be cut. Do not cut into the abdominal cavity. The skin 
can now be separated from the flesh and turned back as far as 
the thigh, which is severed at the joint. When this is done on 
both sides, the gut should be drawn out and severed at a short 
distance from the vent. The tail should also be disjointed at the 
root. This being done, the skin can be loosened around the 
body until the fore-legs are reached, when they also should be 
dissevered. The skinning now proceeds along the neck until 
the skull is reached. Here considerable care is necessary to re- 
move the skin without damage to the ears, eyelids, and lips. 



PRACTICAL TECHNOLOGY. 



165 



The skin is left attached to the skull ; when the operation has 
proceeded far enough to expose the muscles of the jaws, the 
skin must be separated from the body at the first joint of the 
neck. The tongue, eyes, and muscles, remaining attached to 
the head, are now to be carefully removed, and the brain taken 
out from an opening in the back of the skull cut through for 
that purpose. To make this opening, amateurs can use a small 
gimlet or bit with very small animals, and a large one as cir- 
cumstances may demand. The legs are now to be skinned out 
quite down to the claws, which completes the operation of skin- 
ning. During the entire process, all fluids escaping must be im- 
mediately soaked up with cotton. As soon as the skin is re- 
moved, it should be thoroughly rubbed with arsenical soap, not 
omitting the inside of the skull and mouth cavities. 

The following explanation of stuffing relates to a small ani- 
mal such as the squirrel. Provide yourself with cotton, thread, 
and twine, also stuffing-forceps, a pair of pincers, a file, and 
wire-cutters. With the aid of the forceps (a pair of slender- 
jawed pliers), supply the various muscles of the face and head 
by inserting cotton both through the mouth and eyelids. Take 
annealed iron wire and cut off 6 pieces : No. 1, two or three 
inches longer than the total length of the body ; Nos. 2 and 3 
for the fore-legs ; Nos. 4 and 5 for the hind-legs ; each of these 
should be three inches longer than the limbs they are to 
support ; No. 6, for a support for the tail, of the same propor- 
tionate length as the others. With a large pair of scissors, cut 
fine a quantity of tow, and with this, by the use of the long 
forceps, stuff the neck to its natural dimensions. Taking wire 
No. 1, bend it in four small rings, the distance between the two 
outer representing the length of the body taken from the skin, 
a, leaving one long end for a support to the head and neck, & (see 




STUFFING ANIMA 

figure). Mould tow about that part containing the rings, and, 
by winding it down with thread, form an artificial body. 
Sharpen the projecting end of the wire to a fine point with the 
file, and insert it up through the tow in the neck, and thence 
through the skull ; the skin should then be pulled over the 
body. Wires No. 2 and 8 are placed next in position by insert- 
ing them through the soles of the feet, up within the skin 
of the leg, and through the body of tow, until they appear upon 
the opposite side. With the pincers, bend over the end of each, 
forming a hook ; the wires must then be pulled backward, thus 
fastening the hooks firmly into the body. The loose skin of the 
limbs should then be stuffed with cut tow, taking care to imitate 
the muscles of the living subject. Nos. 4 and 5 can be fixed in 
position after the same manner, unless the animal is to rest en- 



166 PKACTICAL TECHNOLOGY. 



tirely upon its rear (as in the case with the squirrel feeding) ; then 
the wire must be inserted at the tarsal joint instead of at the 
sole of the foot. If any depressions appear in the skin, they 
must be stuffed out with cut tow. Wire No. 6 should now be 
inserted at the tip of the tail, and forced down within the skin, 
hooking it into the body in the same manner as the leg-wires. 
Stuff the tail to its proper dimensions with cut tow, and care- 
fully sew up the incision along the abdomen. Having prepared 
a board about f inch thick, pierce in it two holes at the proper 
distance apart for the reception of the wires (four holes will be 
needed if the animal is to stand on all extremities) ; these must 
be drawn through upon the under side until the feet rest close 
upon the upper surface, when they should be clinched. The 
different joints of the limbs can now be imitated by bending 
the wire at the proper points. The eyes should next be placed 
in position, and cemented in the orbits by a little putty. Care 
should be taken in arranging the eyelid, for the expression de- 
pends altogether upon this point. Clip off any superfluous wire 
which may extend above the head with the wire-cutters. The 
specimen should be placed in some locality free from moisture, 
and allowed to dry thoroughly, when it is complete for the cabi- 
net. 



PAINTING, GILDING, AND VARNISHING RE- 
CIPES. 

Balloon Varnishes. — Mr. John Wise, the well-known aero- 
naut, says : ' ' There are two ways of preparing linseed-oil for bal- 
loon varnish : the quick and the slow process. The first is by 
heating the oil up to a temperature at which it will ignite spon- 
taneously. In order to secure it from burning up, it must be 
heated in an iron or copper vessel, with a lid that can be closed 
when it begins to emit dense white vapor. If it is desired to 
have it fast drying, from 4 to 6 ozs. litharge per gallon should be 
boiled in it. This process takes about one hour, and renders the 
oil thick and tough, giving a good body and glossy surface to 
the cloth. The slow process is to boil the oil from 12 to 20 hours, 
keeping it at a temperature of about 200° Fahr., incorporating 
with it, while boiling, ^ oz. sulphate of manganese to each gal- 
lon of oil. These varnishes should be applied to the cloth tole- 
rably hot. There are other formulas, such as the incorporation 
with the oil of some birdlime. Gum-elastic is also used to give 
the oil body and elasticity. When I desire to make a balloon 
extraordinarily close, 1 give it a first coating of compound varnish 
made up of equal parts white glue and glycerine." 

Bronze, GoiiD, for furniture. — Gold bronze for furniture is a 
mixture of copal varnisli mixed with gold-colored bronze-powder. 
The last is bisulphate of tin. 

Bkushes, Care of varnishing. — A good way to keep brushes 



PKACTICAL TECHIS^OLOGY. 167 

is to suspend them by the handles in a covered can, keeping the 
points at least half an inch from the bottom, and apart from each 
other. The can should be filled with slowly-drying varnish up 
to a line about ^q inch above the bristles or hair. The can should 
then be kept in a close cupboard, or in a box fitted for the pur- 
pose. As wiping a brush on a sharp edge will gradually split 
the bristles and cause them to curl backward, and eventually 
ruin the brush, the top of the can should have a wire soldered 
along the edge of the tin, turned over, in order to prevent injury. 
Finishing brushes should not be cleansed in turpentine, except in 
extreme cases. When taken from the can, prepare them for use 
by working them out in varnish ; and before replacing them, 
cleanse the handles and binding in turpentine. 

Colors, Naturally transparent. — These are terra de sienna, 
asphaltum, dragon's bloody carmine, rose-pink, chemical brown, 
all the lakes, gamboge, and all the gums. Semi-transparent : um- 
ber, Vandyke brown, chrome red, emerald green, Brunswick 
green, ultramarine, indigo, and verdigris. Transparent colors are 
purer if ground in water ; allow them to settle, pour off the top 
part of the settlings ; mix that with more water ; let it settle, and 
take the top half of that, which will be free from all sand and 
grit. Turpentine makes transparent colors work crumbly. 
Bleached boiled oil or white varnish is the best vehicle for flow- 
ing evenly. 

Gilding vtithout a Battery. — Dissolve 20 grains chloride 
of gold in a solution of cyanide of potassium, 1 oz. to 1 pint pure 
water. Put the solution of cyanide of gold in a glass or porce 
lain jar ; place in it the articles to be gilded in contact with a 
piece of bright zinc, in the solution near them ; the process will 
be hastened by a gentle warmth. If the gold is deposited on the 
zinc, rub a little shellac-varnish on it. The chloride of gold 
may be prepared by dissolving gold in aqua regia in the propor- 
tions of 16 grains gold to 1 oz. acid, and evaporating to dryness. 

Gilding on Glass. — Mix powdered gold with thick gum- 
arabic and powdered borax ; with this trace the design on the 
glass, and then bake it in a hot oven. The gum is thus burned 
and the borax vitrified, and at the same time the gold is fixed 
on the glass. To make powdered gold, rub down gold-leaf with 
pure honey on a marble slab. Wash the mixture, and the pre- 
cipitate is the gold used. 

Japan, Black and flexible. — Take burnt umber 4 ozs. , asphal- 
tum 2 ozs., boiled oil 2 qts. ; dissolve the asphaltum first in a 
little oil, using moderate heat; then add the umber (ground in oil), 
and lastly the rest of the oil, and incorporate thoroughly. Thin 
with turpentine. 

Loom-Harness, Varnish for. — Mix linseed-oil 2 gals., gum- 
shellac 2i lbs., litharge 2 lbs., red-lead 1 lb., umber 1^ lbs., 
sugar of lead 1^ lbs. 

Machinery, Painting. — The following colors contrast hand- 
somely : 1. Black and warm brown. 2. Violet and pale green. 
3. Violet and light rose-color. 4. Deep blue and golden brown. 
5. Chocolate and bright blue. 6. Deep red and gray. 7. Maroon 



168 PRACTICAL TECHNOLOGY. 



and warm green. 8. Deep blue and pink. 9. Chocolate and pea- 
green. 10. Maroon and deep blue. 11. Claret and buff. 12. 
Black aud warm green. 

Marble, To stain. — Blue, solution of litmus ; green, wax col- 
ored with verdigris ; yellow, tincture of gamboge or turmeric ; 
red, tincture of alkanet or dragon's blood ; crimson, alkanet in 
turpentine ; flesh, wax tinged with turpentine ; brown, tincture 
of logwood ; gold, equal parts of verdigris, sal-ammoniac, and 
sulphate of zinc in fine powder. 

Paint without oil. — Break an egg into a dish and beat slight- 
ly. Use the white only, if for white paint ; then stir in coloring 
matter to suit. Red-lead makes a good red paint. To thin it, 
use a little skimmed milk. Eggs that are a little too old to eat 
will do for this very well. 

Paint, Reddish-brown, for wood. — The wood is first washed 
with a solution of 1 lb. cupric sulphate in 1 gallon water, and 
then with -| lb. potassium ferrpcyanide dissolved in 1 gallon wa- 
ter. The resulting brown cupric ferrocyanide withstands the 
weather, and is not attacked by insects. It may be covered, if 
desired, with a coat of linseed-oil varnish. 

Paint to stand the action of hot water. — Clean the metal 
with turpentine or benzine. Then mix white-lead, carriage- var- 
nish, and spirits of turpentine, and give the metal two thin coats, 
and then a thick coat of white-lead and carriage -varnish, applied 
as quickly as possible. 

Putty, Indestructible. — Boil 4 lbs. brown umber in 7 lbs. 
linseed-oil for 2 hours ; stir in 2 ozs. wax ; take from the fire, 
and mix in 5^ lbs. chalk and 11 lbs. white-lead, and incor- 
porate thoroughly. 

Iron Surfaces, Painting. — In mixing paints for iron surfaces, 
it is of the first importance that the best materials only be used. 
Linseed-oil is the best medium, when free from admixture with 
turpentine. A volatile oil, like turpentine, can not be used with 
advantage on a non-absorbent surface like that of iron, for the 
reason that it leaves the paint a dry scale on the outside, which, 
having no cohesion, can be readily crumbled or washed away. 
Linseed-oil, on the other hand, is peculiarly well adapted for this 
purpose. It does not evaporate in any perceptible degree, but the 
large percentage of linolein which it contains combines with the 
oxygen of the air, and forms a solid, translucent substance, of resi- 
nous appearance, which possesses much toughness and elasticity, 
and will not crack or blister by reason of the expansion and 
contraction of the iron with variations of temperature. It is, 
moreover, remarkably adhesive, is impervious to Avater, and is 
very difficult of solution in essential oils, spirits, or naphtha, and 
even in bisulphide of carbon. Another important advantage of 
linolein is that it expands in drying, which peculiarly adapts it 
to iron surfaces ; since cracks, however minute, resulting from 
shrinkage, expose enough of the metal to aflford a chance for cor- 
rosion, which will spread in all directions, undermining the paint 
and causing it to scale off, beside discoloring it. In selecting a 
paint for iron, mechanical adhesion is a consideration of the first 



PRACTICAL TECHNOLOGY. 169 

importance. Pitchy or bituminous films are especially effective 
as regards their adhesion to iron ; for example, solutions of as- 
phalt or pitch in petroleum or turpentine. These are also very ef- 
fective as regards continuity, owing to the fact that, in drying, 
they form plastic films, which yield with the expansion and con- 
traction of the iron, and manifest no tendency to crack. If the 
surface is rusty, they penetrate the oxide scale, and envelop the 
particles very effectually, making them a portion of the paint. 
The solubility of such a film in water may be counteracted by 
mixing it with linseed-oil. The experiment may easily be tried 
by mixing about 2 parts of Brunswick black with one of white, 
red, or stone colored paint, the body of which is composed of red 
or white lead or litharge. Red-lead is the best, for many reasons, 
if finely ground and thoroughly mixed with linseed-oil. Any one 
of several kinds of bitumen may be used, either natural mineral 
asphalt, pine pitch, or artificial asphalt, such as gas-tar or the re- 
siduum of petroleum distillation, in cases where the crude oil has 
been distilled before being treated with acid. This gives a very 
hard, bright pitch, which is soluble in " once run" paraffine spirit, 
and which makes the base of an excellent, cheap, and durable 
paint for iron- work in exposed positions. Parafl3.ne can be recom- 
mended for all classes of iron-work which can be treated hot. The 
most effective method of applying it is to heat the iron in vacuo, 
in order to expand it and open its pores, when paraffine, raised 
to the proper temperature, is run upon it. By this means the iron 
is penetrated to a sufficient depth to afford a very effectual pro- 
tection against oxidation, especially when a suitable paint is sub- 
sequently applied. 

Lacquer, Deep golden. — Seed-lac 3 oz., turmeric 1 oz., dragon's 
blood i oz. , alcohol 1 pt. Digest for a week, frequently shaking. 
Decant and filter. Golden : Ground turmeric 1 lb., gamboge 1^ 
ozs., gum-sandarac S^lbs., shellac f lb. (all in powder), recti- 
fied spirits of wine, 2 gals. Dissolve, strain, and add 1 pt. of tur- 
pentine varnish. Red : Spanish anatto 3 lbs. , dragon's blood 
1 lb., gum-sandarac 3J lbs., rectified spirits 2 gals., turpen- 
tine varnish 1 qt. Dissolve, strain, and mix, as last. Pale brass : 
Gamboge, cut small, 1 oz. , Cape aloes, ditto, 3 ozs., pale shellac 
1 lb., rectified spirits 2 gals. Dissolve and mix as with the 
golden. Another golden : Ground turmeric 1 lb., gamboge, pow- 
dered, l^ozs., gum-sandarac, powdered, 3i ozs., shellac f lb., 
spirits of wine 2 gals. After being agitated, dissolved, and 
strained, add 1 pt. of turpentine varnish, well mixed. Another 
red: Spirits of wine 2 gals., dragon's blood 1 lb., Spanish anat- 
to 3 lbs., gum-sandarac 4^ lbs., turpentine 2 pts. Make in 
same manner. Another pale brass : Spirits of wine 2 gals., Cape 
aloes, cut small, 3 ozs., pale shellac 1 lb., gamboge, cut small, 
1 oz. ; no turpentine varnish. Make in same manner. Another 
deep golden : Strongest alcohol 4 ozs., Spanish anatto 8 grains., 
powdered turmeric 2 drachms, red-saunders 12 grains. Infuse 
this mixture in the cold for forty- eight hours, pour off the clear, 
and strain the rest ; then add powdered shellac i oz. , sandarac 
1 drachm, mastic 1 drachm, Canada balsam 1 drachm. Dis- 
solve in the cold by frequent agitation, laying the^ bottle on its 
side to present a greater surface to the alcohol. When dissolved. 



170 PRA.CTICAL TECHNOLOGY. 

add 30 drops of spirits of turpentine. Pale tin : Strongest 

alcohol 4 ozs. , powdered turmeric 2 drachms, hay saffron 1 

scruple, dragon's blood, in powder, 2 scruples, red-saunders \ 

scruple. Infuse, and add shellac, etc. , as to the last-described deep 

golden. When dissolved, add 40 drops of spirits of turpentine. 
Lacquer should always stand till it is quite fine before it is 
used. 

Lettering, Sign-painter's scale for. — The following is a con- 
venient table for sign-painters or others who have occasion to 
make lettering. Supposing the height of the capital letters to be 
ten, the widths are as follows : B, F, P, ten ; A, C, D, E, G, H, 
K, N, O, Q, R, T, V, X, and Y, eleven ; I, five ; J, eight ; S and 
L, nine ; M and W, seventeen ; Z and &, twelve. Numerals : 1 
equals five ; 2, 3, 5, 7, 8, nine ; 4, eleven ; 6, 9, 0, ten. Lower- 
case letters (height six and a half) : Width : a, b, d, k, p, q, x and 
z, seven and a half ; c, e, o, s, seven ; f, i, j, 1, t, three ; g, h, n, 
u, eight ; m, thirteen ; r, v, y, six ; w, ten. 

Putty, Old, in sashes, To soften. — Run a red-hot iron over it : 
it will peel off easily. 

Varnish, Black. — Alcohol 1 qt., aniline blue 184.8 grs., 
fuchsin 46,2 grs., naphthaline yellow 123.2. Dissolve by agita- 
tion in less than 12 hours. One application is suificient. The 
mixture should be filtered when it will not deposit. 

Varnish, Cheap gold. — The following is a cheap substitute for 
the expensive gold varnish used on ornamental tin- ware. Tur- 
pentine ^ gallon, asphaltum ^ gill, yellow aniline 2 ozs., um- 
ber 4 ozs., turpentine varnish 1 gal., and gamboge ^ lb. Mix 
and boil for ten hours. 

Varnish, Copal, To make. — Dissolve 1 pt. camphor, by weight, 
in 12 pts. ether, then add best copal resin (pulverized) 4 pts., and 
place in a well-stoppered bottle. When the copal has partly dis- 
solved and has become swollen, add strong alcohol 4 pts., oil of 
turpentine ^ pt. Shake, and allow to stand for a few hours. 
This makes an excellent varnish. 

Varnish for Maps. — Take equal parts genuine Canada balsam 
and oil of turpentine ; mix. Set the bottle in warm water, and 
agitate until the solution is perfect ; then set in a warm place a 
week to settle, when pour off the clear varnish for use. Before 
using, cover the map with a thin solution of pure glue. 

Varnish, Parisian. — Dissolve 1 part of shellac in 3 to 4 parts of 
alcohol of 92 per cent in a water-bath, and add cautiously-distill- 
ed water, until a curdy mass separates out, which is collected 
and pressed between linen. The liquid is filtered through paper, 
all the alcohol removed by distillation from the water-bath, and 
the resin removed and dried at 100^ Centigrade, until it ceases to 
lose weight. Dissolve it in double its weight of alcohol of 96 per 
cent, and perfume with lavender oil. 

Walnut Stain for Wood. — Water 1 qt., washing soda H 
ozs., Vandyke brown 2| ozs., bichromate of potash J oz. Boil 
for ten minutes, and apply with a brush, either hot or cold. 



PRACTICAL TECHNOLOGY. 



171 



Whitewash, To improve. — Add a strong solution of sulphate 
of magnesia. 

Wood, Red stain for. — A permanent and handsome reddish 
color may be given to cherry or pear tree wood by a coat of a 
strong solution of permanganate of potash, left on a longer or 
shorter time according to the shade required. 



HINTS ABOUT DEAWING AND SKETCHING. 

Camera Lucida, The. — This is probably the most reliable op- 
tical device employed for copying. The principle of its construc- 
tion will be understood in the diagram marked 2 in the engrav- 
ing. The glass is simply a four-sided prism, having one right 
angle, one of 135°, and two of 67-^°. When disposed as repre- 
sented, the rays from the object pass into it without any appreci- 
able refraction, and are totally reflected from the lower inclined 




PIG. 1. — THE CAMERA LTJCIDA. 



side, and again from the upper inclined side, emerging near tha 
summit in a direction almost perpendicular to the top face, so 
that the eye sees on the paper placed beneath an image of the 
object. If the image be traced by the pencil, a very correct out- 
line, not reversed, is obtained. The use of the device requires 
practice. The nearer the object copied is brought to the prism, 
the larger is its image, and vice versa. 



172 



PKA.CTICAL TECHNOLOGY, 



A simple method of constructing the camera lucida is shown in 
Fig. 2, and is the invention of Mr. H. 
E. Mead, artist of the Scientific Ame- 
rican. The prism can be obtained at a 
small cost from any optician, and the 
rest of the apparatus any one can cut out 
of black walnut with a knife, and per- 
haps a gimlet. The thumbscrews used 
are of brass, of the kind employed for 
shutter-fastenings, and can be procured 
of any hardware dealer for a few cents 
each. B is the prism, and A is a sec- 
tion of one of the joints, showing how 
the apparatus may be easily adjusted. 
A movable rod, secured by a thumb- 
screw, regulates the height of the prism, 
and the single clamp shown secures it 
to the table. The cost of the whole is 
about one dollar. 

Dra wing-Board, Reflecting.— A flat 
board is provided, with two uprights, 
both of which, with the board, are 
grooved to hold a pane of glass in a per- 
pendicular position. The drawing to be 
copied is secured to the board on the left 
of the glass, and the blank paper is fas- 
tened on the right. The artist now 
CAMERA stands to the left, as represented in the 
illustration, and - looks down upon the 
glass at a very oblique angle. The original drawing is re- 
flected from the polished surface of the pane to his eye, and at 
the same time he sees the white paper through the transparent 
glass, so that the lines of the model appear transferred, but 
reversed, upon the paper. These are followed with a pencil, 
and the outline is made. 

Drawing, Colors used in mechanical. — The annexed table 
shows different materials, and the colors used to denote them : 
Cast-iron, . . . Paine's gray and a little Indian ink. 
" (another tint) Ordinary neutral tint. 
" *' Prussian blue and Indian ink. 

Wrought-iron, . . Prussian blue (or cobalt). 
Steel, . . .A purple made by mixing crimson lake 

and Prussian blue. 
Gun-metal, . . Gamboge or yellow cadmium. 

Copper, . . . Indian red mixed with a little lake. 
Wood, . . . Burnt umber. 

Brick (red), . . Indian red. 

" (yellow), . . Indian yellow or cadmium, toned with 

white. 
Stone color, . . Chinese white and Indian ink, toned 

with yellow. 
Water, . . . Broken, irregular straight lines, with 

liquid copperas. 




PIG. 2. 



-A SIMPLE 
LUCIDA. 



PRACTICAL TECHNOLOGY, 



173 



Paper, Transfer. — A good transfer paper for copying monu- 
mental inscriptions and metallic patterns may be made by rubbing 




A REFLECTING DRAWING-BOARD. 

a mixture of black-lead and soap over the surface of common 
silver paper . 

Paper, Tracing, Temporarily transparent. — This is made by 
dissolving castor-oil in absolute alcohol, and applying the liquid 
to the paper with a sponge. The alcohol speedily evaporates, 
leaving the paper dry. After the tracing is made, the paper is 
immersed in absolute alcohol, which removes the oil, restoring 
the sheet to its original opacity. 

Paper, Tracing, that can be washed. — This is prepared by 
first saturating writing-paper with benzine, and then immedi- 
ately coating it lightly with a v'arnish composed of boiled bleached 
linseed-oil 20 parts, lead shavings 1 part, oxide of zinc 5 
parts, Venice turpentine ^ part. Mix, boil for 8 hours, and, 
after cooling, add white gum- copal 5 parts, and gum-sandarac ^ 
part. 

Pantagraph, The. — This consists of four rulers, jointed toge- 
ther at their intersections, and having, at two of the angles, sup- 
ports terminating in round points or smoothly-running casters. 
At one of the other angles is a weight to which the apparatus is 
pivoted, and which holds it in place, and at the fourth corner is 
a tracinor-point, shown in the hand of the operator. Directly 
across the frame thus made, and pivoted at its ends to the centres 
of two of the bars, is a fifth bar, through the middle of which 
passes a pencil. Along half the length of the two side-bars, and 



174 



PRACTICAL TECHNOLOGY. 



also of the central bar, are made perforations, so that the length 
of the rulers can be shortened as rendered necessary. The tracing 
point is moved over the outline to be followed, and its motion is 
communicated to the series of rulers, which, by a kind of paral- 
lel movement actuate the pencil to describe precisely the same 




THE PANTAGRAPH. 



line, equal in dimension to that of the copy, or enlarged or re- 
duced. The scales of the two drawings are to each other as the 
distances of the pencil and of the tracing-point from the pivot, 
and these distances are adjusted by altering the position of the 
joints in the holes. 

Pencils, Copying, To make. — Pencils are sold by stationers, 
the marks of which may be copied in the same manner as writing 
made by the pen with ordinary copying-ink. The method of 
preparing the leads is as follows : A thick paste is made of gra- 
phite, finely pulverized kaolin, and a very concentrated solution 
of aniline blue, soluble in water. The mixture is pressed into 
cylinders of suitable size and dried, when it is ready for use. Gum- 
arabic may be substituted for the kaolin. 

Sun Drawing. — Draw with a pencil on a piece of tracing- 
paper the desired design ; go over the lines with very black ink, 
turn the paper over, and follow the lines also with ink on the 
reverse side ; fasten the paper by the corners to a pane of clear 
glass. Make a solution of ^ oz. bichromate of potash in 2 ozs. 
hot water, strain when cold, and with this brush over the paper 
or silk on which tlie design is to be printed. Place the material 
thus prepared under the paper on the glass, and clamp all together. 
Expose the whole to bright sunlight, glass uppermost, then design, 
then bichromate paper ; in a few moments, the design will be print- 



PRACTICAL TECHNOLOGY. 



175 



ed deeply. Wash and soak for a short time in clean water (to 
fix), dry, and press with a warm flat-iron. 

Ruler, Perspective. — This is a simple arrangement for draw- 
ing lines in correct perspective. It consists in three arms of 
equal length pivoted together at one end by a screw-clamp. Two 
pins are inserted in the drawing-board, against which two arms of 
the ruler abut. The angle of these arms and the position of the 
pins are governed by the distance required for the vanishing- 




THE PEBSPECTIVE-RULER. 

point, as the greater the angle, the further the same is removed, 
and vice versa. Once adjusted, the parts are clamped firmly to- 
gether, and the lines ruled by the upper side of the arm which 
rests upon the paper. The arms at an angle are kept in contact 
with the pins, and the ruling arm is moved up or down the paper. 

Sketching-Frames. — A square frame is hinged to the top of 
an ordinary drawing lap-board, so that it will stand in an upright 
position (as in Fig. 1). Across this is stretched a number of 
threads or wires at equal distances apart so as to divide the inte- 
rior space into small squares. The paper on the board is simi- 
larly divided by light pencil-lines ruled over the surface. In 
making the sketch, the artist draws so much of the view as he 
sees through one of his squares in the frame, into the correspond- 
ing ruled square on the paper, and thus having a large number 
of straight lines to refer to is very readily enabled to locate the 
details of the picture. It is, however, necessary to use but one 
eye when looking at the landscape, and to keep this eye always 
at the same place, for which purpose an additional eye -piece 
may be added, simply consisting of a ring supported on a stand. 

Sketching, Out -Door, Simple apparatus for. — Provide a 



176 



PRACTICAL TECHNOLOGY. 



small table with drawer ; mount two grooved movable uprights 
at one end, with glass between the grooves ; place an upright 
with a small eye-hole at the opposite end of the table, as shown 
in the engraving. Wash the glass with a thin solution of gum- 




THE SKETCHING-FRAME. 



arable and rock candy (20 parts ^um to 1 of candy). When the glass 
is dry, it is ready for use. Look through the small hole to get the 
object subtended by the glass, and with a soft crayon outline the 
subject on the prepared surface ; remove the glass and lay it 




OUT-DOOR SKETCHING APPARATUS. 



over your sketch. If you require the outline, you should have a 
second plate of glass, and trace over it the reverse way witli 
charcoal, then lay your paper on, and a little gentle rubbing will 
transfer the outline. 



PRACTICAL TECHNOLOGY. 



177 



Tracing-Table, Transparent. — This, as shown in the illus- 
tration, consists of a square-bottomed box, the tops of the sides of 
which are inclined like those of a writing-desk. The back is open, 
and, as the apparatus rests on the table, abuts against a window. 
The window- shade is drawn down to meet the upper part of the 
device, so that the light enters through the back of the latter. 




A TRANSPAKENT TRACING-TABLE. 



and the interior, being lined with white paper, is reflected up 
through the inclined glass top ; the original drawing is laid upon 
the glass, and a sheet of tissue-paper ruled off in squares is 
placed above it. Being brilliantly illuminated from below, the 
drawing would readily show through, and might be copied, square 
by square, as before described. 



178 PRACTICAL TECHNOLOGY. 



SIMPLE GALVANIC BATTERIES AND ELECTRO- 
PLATING RECIPES. 

Battery Carbons. — These can be readily cut with a hand- 
saw moistened in water. 

Battery, Daniell's, Substitute for copper in. — Brighten sheets 
of ordinary sheet-tin and plunge into a very weak copper-plating 
solution, in connection with a galvanic battery of very low quan- 
tity. In 15 or 18 hours a tenacious film of copper will have been 
deposited upon the tin, and the plate can then be bent in shape 
suitable for the battery. 

Battery, Galyanic, A cheap.— Mr. W. M. Symons proposes 
a cheap but convenient galvanic battery : each of the zinc plates 
is 2 in. square, and covered with fustian or other fabric, out- 
side which thick copper wire is wound to form the other plate ; 
the exciting liquid is weak chloride of zinc. Pairs of plates 
thus made can be arranged in series to form a battery to give out 
weak currents for a great length of time. 

Battery, Galyanic, A simple. — Take a glass tumbler, and 
place in the bottom a sheet of copper, having an insulated wire 
attached and extending out of the tumbler. Cover the copper 
with blue vitriol, and suspend a sheet of zinc near the top. Fill 
the tumbler with water. Connect the zinc and copper together 
for 48 hours, and the battery will be ready for use. 

Battery, Galyanic, Exciting liquid for. — Dissolve protosul- 
phate of iron, 20 pts., by weight, in 36 pts. of water, stir in a 
dilution of sulphuric acid (equal parts of acid and water,) 7 pts., and 
add 1 part nitric acid similarly diluted. This liquid has great 
energy, and disengages no deleterious fumes. 

Battery Zincs, Amalgamation of . — The simplest and quickest 
method consists in immersing the zinc in a liquid composed of 
nitrate of mercury and hydrochloric acid. A few moments are 
sufficient for the complete amalgamation of the zinc, however 
soiled its surface may be. With a quart of this liquid, which 
costs less than 50 cents, 150 zincs can be amalgamated. The 
liquid should be prepared in this manner : Dissolve in warm 
water 200 grains of mercury in 1000 grains of aqua regia (nitric 
acid 1 part, hydrochloric acid 3 parts). When the mercury is 
dissolved, add 1000 grains of hydrochloric acid. 

Electro-Magnets, Softening. — Magnets or armatures for 
electro-motors may be softened as follows : Heat the iron to an 
even dull-red heat all over ; and if the surface of the iron has 
not been faced off in a machine, lightly file it to remove the scale, 
and then immerse it in common softsoap, allowing it to remain 
therein until it is quite cold. Then reheat the magnet to an even 
red heat whose redness is barely perceptible, and bury it in pul- 
verized lime, wherein it must also remain until quite cold, when 
the metal will be found as soft as it is possible to make it, and 
the blade of an ordinary penknife will cut it. At the second 
heating, the iron will emit a light blue flame, showing the effect 



PRACTICAL TECHNOLOGY. 179 

of the immersion in tlie softsoap. Tlie capability of receiving 
strong magnetic power may be, by this process, very much in- 
creased. 

Electro-Plated Paper or Cloth. — Make a solution of ni- 
trate of silver, and add ammonia until the precipitate formed at 
first is entirely dissolved. Place the paper or cloth for 1 or 2 
hours in the liquid. After removing and drying, expose to a 
current of hydrogen gas, by which the silver is reduced to a 
metallic state, and the paper or fabric becomes so good a conduc- 
tor of electricity, that it may be electro-plated vrith copper, silyer, 
or gold in the usual manner. 

Electro-Plating, Cleansing metals for. — Most articles are 
rapidly cleaned by chemical means. The first of these is the re- 
moval of grease by boiling in a solution of caustic soda, made by 
boiling 2 lbs. of common washing-soda and ^ lb. quicklime in a 
gallon of water ; after this they should be well brushed under 
water. The further processes will depend upon the nature of the 
objects. 

1. Silver is washed in dilute nitric acid, then dipped for a mo- 
ment in strong nitric acid, and well washed. Care must betaken 
that the water does not contain chlorine salts ; if the ordinary 
supply does so, the first rinsing after acids must be made in wa- 
ter prepared for the purpose by removing the chlorine by adding 
to it a few drops of nitrate of silver, and allowing the chloride to 
settle. 

2. Copper, brass, and German silver are washed in a pickle of 
water 100 parts, oil of vitriol 100 parts, nitric acid (sp. gr. 1.3) 50 
parts, hydrochloric acid 2 parts. . Spots of verdigris should be 
first removed by rubbing with a piece of wood dipped in hydro- 
chloric acid ; they are then rinsed in water. 

3. Britannia metal, pewter, tin, and lead can not be well clean- 
ed in acids, but are to be well rubbed in a fresh solution of caus- 
tic soda, and passed at once, without washing, into the depositing 
solution, which must be alkaline. 

4. Iron and steel are soaked in water containing 1 lb. oil of 
vitriol to the gallon, with a little nitric and hydrochloric acids 
added. Cast-iron requires a stronger solution, and careful rub- 
bing with sand, etc., to remove scale and the carbon left by the 
acids. It is an advantage at times to connect them to a piece of 
zinc while cleaning. These metals should be cleaned just before 
placing in the depositing cell ; and if they are placed in an alka- 
line solution, they should be rinsed and dipped in a solution of 
caustic soda, to remove all trace of acids. 

5. Zinc may be cleaned like iron, with a dip into stronger acids 
before the final washing. 

6. Solder requires special care, as the acids used with the ob- 
jects produce upon it an insoluble coating, and an obstinate resist- 
ance to deposit is set up at the edge of the solder. The same 
remark applies to soft-metal edgings and mounts. These should be 
rubbed with a strong caustic-soda solution, rinsed, and then 
treated as follows : Make a weak solution of nitrate of copper 
by dissolving copper in dilute nitric acid ; to a camel-hair 
or other soft brush, tie 3 or 4 fiine iron wires to form part of the 



180 PRACTICAL TECHNOLOGY. 

brush ; dip this in the nitrate of copper, and draw over the solder, 
taking care that some of the iron wires touch it ; a thin adherent 
of copper will form, and upon this a good deposit will take place. 
7. Old work for replating must have the silver and gold care- 
fully removed ; if this is not done, there is apt to be a failure of 
contact at the edges of the old coatings, which causes blisters 
and stripping under the burnisher. The best mode of stripping 
is with the scratch-brush, etc., but chemical means may be used. 
Gold is dissolved by strong nitric acid, to which common salt is 
gradually added ; it may be collected afterward by drying and 
fusing with soda or potash. Silver is similarly dissolved by 
strong sulphuric acid and crystals of saltpetre, and recovered by 
diluting and precipitating with hydrochloric acid, then reducing 
the chloride either by fusion with carbonate of soda, or by acid 
and zinc cuttings. Copper can be removed from silver by boiling 
with dilute hydrochloric acid, and tin and lead by a hot solution 
of perchloride of iron. 

Insulators, Rubber, Substitutes for.— Ivory and guaiacum 
wood, which are both relatively good conductors, become nearly 
non- conductive if stove- dried and saturated with certain oily and 
resinous liquids, which close up the pores of the bodies in ques- 
tion, and prevent moisture from penetrating within. Other kinds 
of wood can be modified in the same manner. 

Sawdust of hard wood, agglutinated with blood and submitted 
to a considerable pressure, so as to mould it into a solid, tenacious 
body, is a good insulator for voltaic currents. After remaining 
six days in a damp cellar, it showed no galvanometric deviation. 

Ikon, Electro-plating with silver on. — The direct way' : The ar- 
ticle should first be rendered free from rust by rubbing with em- 
ery-cloth, or by dipping it into a pickle composed of sulphuric acid 
2 ozs., hydrochloric acid 1 oz., water 1 gal. After the article has 
remained some time in this pickle, it should be taken out and the 
rust removed by a brush and wet sand. If the oxide can not be 
easily cleaned off, it must be returned to the pickle. As soon as 
the article is rendered bright, it is washed in a warm solution of 
soda, for the purpose of removing all grease. Lastly, it is well 
rinsed in hot water, and immediately placed in the plating solu- 
tion, which should contain only about one fourth as much silver 
as that used for plating copper and brass articles. The battery 
power must also be weak. When the object receives a slight 
coating, the process may be carried on more rapidly by increasing 
the battery power, and by placing the article in a much stronger 
plating bath, using about 1 oz. silver in a gallon of solution. 
The indirect method consists in first coating the iron with copper, 
which insures success. Copper adheres firmly to iron, but silver 
does not ; hence copper acts the part of a go-between. After the 
article has been cleaned, as above described, it is coated with 
copper by placing it in a solution composed of carbonate of potas- 
sa 4 ozs., sulphate of copper 2 ozs., liquid ammonia about 2 oz., 
cyanide of potassium 6 ozs., water about 1 gal. The sulphate 
of copper may be dissolved in warm rain-water, and, when cold, 
the carbonate of potassa and ammonia added ; the precipitate 
when formed is redissolved. The cyanide of potassium should 



PIIACTICAL TECHNOLOGY. l8l 

now be added, until the bluish color disappears. Should any pre- 
cipitate be found in the bottom of the vessel, the clear solution 
may be poured off from it. The solution is worked cold, and with 
moderate battery power. Let the article remain in the bath 
until a thin film of copper is deposited, then remove quickly, 
rinse in hot water, and place in the silvering solution, where 
the process may go on as rapidly as if plating a copper article. 

Pewter, Electro-plating. — Take 1 ounce nitric acid, and drop 
pieces of copper in it until effervescence ceases ; then add ^ ounce 
water, and the solution is ready for use. Placfe a few drops of 
the solution on the desired surface, and touch it with a piece of 
steel, and there will be a beautiful film of copper deposited. The 
application may be repeated if necessary, though once is general- 
ly sufficient. The article must now be washed and immediately 
be placed in the plating bath, when deposition will take place 
with perfect ease. 

Steel, Magnetization of. — If a properly-tempered steel needle be 
introduced into a magnetizing bobbin connected with a battery of 
constant current, battery and bobbin comprising the circuit, it ac- 
quires a total determined magnetism at the end of a period which 
appears not to exceed that of its introduction. On slowly with- 
drawing the needle, it is found to retain residual magnetism, which, 
together with the total magnetism, increases with each repeated 
introduction until a limit is reached. The needle may be mag- 
netized in the bobbin by three other methods : 1. Establishment : 
Introduce the needle ; establish the current ; slowly withdraw 
the needle. 2. Interruption : With a closed circuit introduce the 
needle slowly ; break the current and withdraw the needle. 3. 
Instantaneous charge : Introduce the needle ; establish and 
break the current ; withdraw the needle. Repetitions of any of 
these three processes (all things being equal) insure an augmen- 
tation of the needle's magnetic moment. The last method is the 
best, but care must be taken to introduce the needle and current 
always in the same position, so as not to reverse the poles. 



USEFUL CHEMICAL RECIPES FOR DETECTION 
OF ADULTERATIONS, FILTERING, INK-MAKING, 
ETC. 

Beer, To prevent, from turning sour while on draft. — A 
slate cistern is made, having a wooden lid, fitting accurately, 
floating on»the surface of the liquid. The sides of the lid are be- 
veled, so that a sharp edge is presented to the walls of the cistern, 
and along this edge a strip of india-rubber is fastened, which 
forms, with the bevel on the upper side, a V-shaped space, into 
which wet sand is packed in order to keep the rubber in close 
contact with the sides of the cistern, and so to exclude the air 
from the same. A hole is formed in the lid, having a stuffing-box, 
through which a pipe passes into the liquid, and the connection 



182 PRACTICAL TECHNOLOGY. 

to the beer-engine is made in the usual way. The end of the pipe 
in the liquid is closed, but perforations are made in the sides 
about an inch therefrom : this prevents any sediment escaping 
with the fluid. Atmospheric pressure, acting on the lid, forces 
it to descend as the liquid is removed from under it, and thus a 
constant flow is obtained by means of the engine. By letting 
the cistern into the ground, the temperature of the liquid will 
remain nearly uniform the year round. 

Beer, To clarify. — Take isinglass, finely shredded, 1 lb., sour 
beer, cider, or vinegar 3 or 4 pints ; macerate together till the 
isinglass swells, and add more of the sour liquid until a gallon 
has been used. Strain and further dilute. A pound of good 
isinglass should make 12 gallons finings, and 1^ pints finings is 
enough to clear a barrel of beer. 

Bisulphide of Carbon, To deodorize. — Distill with quicklime, 
the two substances having been in contact for 24 hours. The 
distillate is received in a flask partially filled with clean copper 
turnings. The lime remaining in the retort is strongly colored. 

Camphor, To powder. — Take camphor 5 ozs., alcohol 5 fl. 
drachms, glycerine 1 fl. drachm. Mix the glycerine with the al- 
cohol, and triturate it with the camphor until reduced to a fine 
powder. 

Candles, Paraflane. — To dye beautiful red, purple, or violet 
tints, use aniline colors. 

Casks, Mouldy, To disinfect. — Wash first for about 5 minutes 
with an alkaline solution of soda, and then soak for 1 or 2 days 
with a liquor acidulated with hydrochloric acid. 

Chloroform, Purifying decomposed. — Shake up the chloro- 
form with a few fragments of caustic soda. 

Dyeing Leather Yellow. — Picric acid dyes leather a good 
yellow, without any mordant ; it must be used in very dilute 
solution, and not warmer than 70° Fahr. Aniline blue modifies 
this color to a fine green. 

Dyes, Testing, for Adulteration. — Red dyes must neither 
color soap-and- water nor lime-water, nor must they themselves 
become yellow or brown after boiling. This test shows the 
presence or absence of Brazil-wood, archil, saffiower, sandal- 
wood, and the aniline colors. Yellow dyes must stand being 
boiled with alcohol, water, and lime-water. The most stable 
yellow is madder-yellow ; the least stable are anatto and tur- 
meric ; fustic is rather better. Blue dyes must not color alcohol 
reddish, nor must they decompose on boiling with hydrochloric 
acid. The best purple colors are composed of indigo and cochi- 
neal, or purpurine. The former test applies also to tliein. Orange 
dyes must color neither water nor alcohol on boiling ; green, 
neither alcohol nor hydrochloric acid. Brown dyes must not 
lose their color on standing with alcohol, or on boiling with water. 
If black colors have a basis of indigo, they turn greenish or blue 
on boiling with sodium carbonate ; if the dye be pure gall-nuts, 
it turns brown. If the material changes to red on boiling with 
hydrochloric acid, the coloring matter is logwood without a basis 



PRACTICAL TECHNOLOGY. 



183 



of indigo, and is not durable, 
present. 



If it changes to blue, indigo is 




A SIMPLE FILTER. 



Filtering, Hot. — The apparatus consists of a tube of soft 
sheet-lead, which can be wound around the funnel containing 
the filter in the form of a spiral. One end ot* the tube passes 
through a cork in the neck of a flask, in which water, or other 
liquid of higher boiling-point, is boiled ; the other end dips into 
a receiver, into which the condensed liquid flows. 

Filter, A simple. — The engraving represents a very good 
filtering apparatus. The best 
material for the box would 
be soapstone ; the next best 
material, iron. Mott's cast- 
iron tank-plates come of a con- 
venient size — 18 X 18 inches 
and 9 X 18 inches. These may- 
be galvanized or coated with 
slate-paint. 

Freezing-Powders. — (1) 
Four pounds sulphate of soda, 
2^ pounds each of muriate of 
ammonia and nitrate of pot- 
ash ; when about to use, add 
double the weight of all the 
ingredients in water. (2) Equal parts of nitrate of potash and 
muriate of ammonia ; when required for use, add more than dou- 
ble the weight of water. (3) Nitrate of ammonia and water in 
equal proportions. (4) Carbonate of soda and nitrate of am- 
monia equal parts, and 1 equivalent of water. 

Filters, To make charcoal. — One method consists in pulveriz- 
ing animal charcoal until reduced to an impalpable powder. This 
is mixed with a definite proportion of Norway tar and a com- 
pound of other combustible substances. The combined materials 
are then properly amalgamated with liquid pitch, and the whole 
kneaded up into a homogeneous plastic mass which admits of 
being moulded into slabs or blocks of any required dimensions 
and shape. These blocks, having been allowed to dry and harden, 
are subsequently carbonized by being subjected to a process of 
incineration by heat ; and in this manner all the combustible 
ingredients are burned out, leaving nothing behind but the 
animal charcoal in the form of a block of charcoal, permeated 
throughout by innumerable pores. 

Gases, Drying. — Anhydrous phosphoric acid is the best sub- 
stance known for this purpose. 

Glycerine, Adulteration of, with sugar and dextrine. To detect. 
— To 5 drops of glycerine add 100 to 120 drops of water, 0.4 to 0.6 
grain of ammonium molybdate, 1 drop pure nitric acid, and boil 
for a minute and a half. If any sugar or dextrine is present, the 
mixture will assume a deep-blue color. 

Glycerine, Purification of. — To purify glycerine which has 
been for some time in use, add 10 lbs. iron-filings to every 100 
lbs. of the impure liquid. Occasionally shake it and stir the 



184 PRACTICAL TECHNOLOGY. 

iron. In the course of a few weeks, a black gelatinous mass will 
collect on the bottom of the vessel, and the supernatant liquid 
will become perfectly clear, and can be evaporated to remove any 
excess of water that may have been added to it. 

Glycerine, Testing. — When treated slowly with sulphuric 
acid, it should not turn brown ; with nitric acid and nitrate of 
silver, it should not become cloudy ; and when rubbed between 
the fingers it should not emit a fatty smell. 

Hides, To preserve. — Carbolic acid is used in South- America 
and Australia for this purpose. The immersion of hides for 24 
hours in a two per cent solution of carbolic acid, and subsequent- 
ly drying them, has been successfully substituted for the more 
tedious and expensive process of salting. 

Hydrocarbons, Classification of. — The classification usually 
adopted by distillers is as follows : All above 88° of Baume's 
hydrometer is called chymogene, from 88° to 70° gasoline, from 
70° to 60° naphtha, from 60° to 50° benzine, from 50° to 35° kero- 
sene, from 35° to 28° lubricating-oil. 

Ink, Blue. — Prussian-blue 6 parts, oxalic acid 1. Mix with 
water to a smooth paste. Dilute with rain-water, and add a 
little gum-arabic to prevent spreading. 

Ink, Copying, used without a press. — Coarsely-broken extract 
of logwood 1 oz., carbonate of soda (crystallized) 1 drachm : heat in 
a porcelain capsule with 8 ozs. distilled water until the solution 
is of a deep-red color. Remove from fire and stir in glycerine 1 oz., 
neutral chromate of potash dissolved in a little water 15 grains, 
and a mucilaginous solution of 2 drachms finely-pulverized 
gum-arabic. Keeps well, never requires a press for copying, and 
does not attack steel pens. The impression is taken on thin 
moistened copying-paper, at the back of which is placed a sheet 
of writing-paper. 

Ink from Elderberries. — Bruise the berries, place them in 
an earthen vessel, and keep in a warm place for 3 days. Press 
out and filter. Add to 12^ ozs. of this filtered juice 1 oz. sulphate 
of iron and the same quantity of pyroligneous acid. This ink is 
violet at first, and afterward becomes black. 

Ink, Indelible, for marking linen.— (1) Bichloride of copper, 8^ 
grains, dissolved in distilled water, 30 grains ; then add common 
salt, 10 grains, and liquid ammonia, 9k grains. A solution of 30 
grains hydrochlorate of aiiirline in 20 grains distilled water is 
then added to 20 grains solution of gum-arabic, containing 2 pts. 
water, 1 pt. gum-arabic, and 10 grains glycerine. Four parts of 
the aniline solution thus prepared are mixed with 1 part of the 
copper solution. This ink can be used with a steel pen. It is 
green at first, but becomes black in a few days or by application 
of hot iron. It is absolutely indelible, and the finest devices can 
be written with it. It is better to mix the two solutions only 
just before using. (2) For very fine linen, take a solution of 
nitrate of silver, 4 pts., in distilled water, 24 pts. Add liquid 
ammonia until the precipitate formed is dissolved. Then a little 
sap-green and indigo are ground together and mixed with a so- 
lution of gum-arabic, 4 pts. , and this is mixed with the nitrate 



PRACTICAL TECHN^OLOGY. 185 

of silver solution. Tlie whole is then diluted until it occupies 32 
parts. It turns black as No; 1 does. 

Ink, To restore dim. — Cover the letters with solution of ferro- 
cyanide of potassium, with the addition of diluted mineral acid 
(muriatic) ; upon the application of which the letters will change 
to a deep-blue color. To prevent the color from spreading, the 
ferrocyanide should be put on first, and the dilute acid added 
upon it. 

Inks, Aniline. — Violet ink is obtained by dissolving one part 
of aniline violet-blue in 300 parts of water. This ink is quite 
limpid, dries quickly, and gives a remarkably dark color. It is 
necessary that new pens should be employed in using it, as the 
smallest quantity of ordinary ink mixed with it causes its altera- 
tion. Blue ink is made by dissolving 1 part of soluble Paris-blue 
in 250 parts of boiling water ; red ink, by dissolving 1 part of soluble 
fuchsin in 200 parts boiling water. While ordinary inks are 
decomposed by numerous substances, and notably by hydrochloric 
acid, aniline inks are completely ineffaceable from the paper on 
which they are used. They resist the action of acids, and even 
of chlorine. 

Inks, Sympathetic. — Yelloics (1): Sulphate of copper and sal- 
ammoniac, equal parts, dissolved in water ; (2) onion-juice ; both 
visible on heating Black (1) : Weak infusion of galls. This is 
turned black by weak solution of protosulphate of iron. (2) 
Weak solution of protosulphate of iron. Turns blue when 
moistened by weak solution of prussiate of potash, and black by 
infusion of galls. Brown : Very weak solutions of nitric, sulphu- 
ric, muriatic acids, common salt, or nitrate of potash. Visible on 
heating. Green : Solution of nitro-muriate of cobalt. Brought 
out by heat ; fades when cool. Rose-red : Acetate of cobalt solu- 
tion, with a small quantity of nitrate of potash. Acts as pre- 
ceding. Solutions of nitrate of silver and terchloride of gold 
become permanently dark when exposed to sunlight. 

Ink, White, for colored paper. — 1 part muriatic acid, and 20 
parts starch-water. Very dilute oxalic acid may also l3e used. 
Write with a steel pen. 

Ivory and Bones, Bleaching. — Spirit of turpentine is very 
efficacious in removing the disagreeable odor and fatty emana- 
tions of bones or ivory, while it leaves them beautifully bleach- 
ed. The articles should be exposed in the fluid for 3 or 4 
days in the sun, or a little longer if in the shade. They should 
rest upon strips of zinc, so as to be a fraction of an inch above 
the bottom of the glass vessel employed. The turpentine acts 
as an oxidizing agent, and the product of the combustion is an 
acid liquor which sinks to the bottom, and strongly attacks the 
bones if they be allowed to touch it. The action of the turpen- 
tine is not confined to bones and ivory, but extends to wood of 
various varieties, especially beech, maple, elm, apd cork. 

Ivory, Imitation. — To liquid chloride of zinc of 50° to 60° 
Baume, add 3 per cent of sal-ammoniac ; then add zinc- white until 
the mass is of proper consistence. This cement may be run into 
moulds, and when hard becomes as firm as marble. 



186 PRACTICAL TECHKOLOGY. 

Light, brilliant white, To make a. — Fill a small vessel of 
earthenware or metal with perfectly dry salpetre or nitre, press 
down a cavity into its surface, and in this cavity place a piece of 
phosphorus ; ignite this, and the heat given off melts a sufficient 
quantity of the nitre to evolve oxygen enough to combine with 
the phosphorus, and the effect is to produce the most magnificent 
white light which chemistry can afford. 

Mica. — The best comes from the Eastern States. New- York 
mica is good. Canada mica is of several different shades, from 
light brown to intensely black. 

Oil, Cotton- Seed, Refining. — One hundred gallons of the crude 
oil are placed in a tank, and 3 gallons of caustic potash-lye, of 
45° Baume, are gradually added and well stirred for several 
hours ; or the same quantity of oil is treated with about 6 gallons 
of soda-lye of 25° or 30° Baume, and heated for an hour or more 
to about 200° or 240° Fahr., under perpetual stirring, and left to 
settle. The clear yellow oil is then separated from the brown 
soap stock, and this dark soap sediment is placed into bags, 
where the remainder of the oil will drain off ; and the sediment 
has a marketable value of 3 or 4 cents a po.und for soap-makers. 
The potash-lye has to be made in iron pots, but the oil and lye 
may be mixed in wooden tanks. 

Oils from Plants, odoriferous. Extraction of. — This can be 
done by glycerine. The flowers are introduced into the liquid 
and left for 3 weeks. The glycerine is then drained off, and 
may be dissolved in all proportions in alcohol or water to make 
perfumed liquids or washes. 

Oils, Lubricating, Testing for acids in. — Dissolve a crystallized 
piece of carbonate of soda about as large as a walnut in an equal 
bulk of water, and place the solution in a flask with some of the 
oil. If, on settling after thorough agitation, a large quantity of 
precipitate forms, the oil should be rejected as impure. As oils 
are often clarified and bleached with acids, which injure the 
metals on which they are used, this is an important point to 
know. 

Oil, Sperm, To prevent gumming. — It may be purified by agi- 
tating 100 parts oil with 4 parts chloride of lime and 12 water ; 
a small quantity of decoction of oak-bark is afterward added to 
remove all traces of gelatinous matter which it retains, and the 
mixture is left to settle. The clear oil is afterward agitated 
with a small portion of sulphuric acid, again clarified by subsi- 
dence, and washed to remove adhering sulphuric acid. The ad- 
dition of mineral oils, as heavy kerosene, has also the tendency 
to prevent gumming, or at least greatly to diminish it. 

Oils, Volatile, Explosion of. — A mixture of 2 parts of perfectly 
dry permanganate of potassium with 2- or 3 parts of concentrated 
sulphuric acid is a most powerful oxidizing agent, owing to the 
separation of permanganic acid and its imuied.ate decomposition 
with the liberation of oxygen. Volatile oils are violently affect- 
ed by this mixture, if about 10 drops are placed in a little dish 
and then touched with a stout glass rod previously dipped into 
the mixture. The following produce explosions, often most vio- 



PRACTICAL TECHiq^OLOGY. 187 

lently : oils of tliyme, mace, turpentine (rectified), spike, cinna- 
mon, origanum, rue, cubebs, and lemon. The following oils are 
simply inflamed, particularly if poured upon* blotting-paper and 
touched with the mixture, though under certain still unknown 
circumstances explosion m.ay occur : oils of rosemary, lavender, 
cloves, rose, geranium, gaultheria, caraway, cajeput, bitter- 
almond, and rectified petroleum. The following* substances are 
ignited without explosion : alcohol, ether, wood-spirit, benzole, 
clilorelayl, sulphide of carbon, and cotton. Gun-cotton and gun- 
powder are not ignited. 

Petroleum, Test for illuminating. — Fill a tumbler full of 
water at 110° Fahr. Stir in a tablespoonful of the oil to be tested, 
and leave until the oil reaches about the same temperature. Pass 
a lighted match over the oil as it floats on the surface. If the oil 
does not ignite, it can be safely used ; if it does, discard it, how- 
ever cheap the price may be. Improved test proposed by Dr. Van 
der Weyde : Fill af narrow test-tube with the petroleum to be 
tested, close it with the flnger, invert it, and plunge entirely in 
water of some 140° Fahr. ; wait until the temperature has 
descended to 110° ; if then any gas-bubbles are seen in the 
closed upper part of the test-tube the oil contains dangerous in- 
flammable vapors. As all vapors of petroleum are inflammable, 
it is not necessary to ignite them ; the demonstration of their 
presence in this way is sufficient to condemn such oil. 

Kaw Hide, To dissolve. — This can be done completely in water 
heated under pressure. 

Resins, Solubility of. — Copal, amber, dammar, colophony, 
lac (or shellac), elemi, sandarac, mastic, and carnauba wax (a 
resin) have been experimented upon. Amber, shellac, elemi, 
sandarac, and mastic swell up and increase in bulk when heated ; 
the others fuse quietly. Carnauba wax melts in boiling water, 
colophony becomes pasty therein, while dammar, shellac, elemi, 
and mastic agglutinate. Copal, amber, and sandarac do not 
change in water. 

Alcohol does not dissolve amber or dammar ; it ago^lutinates 
copal, and partly dissolves elemi and carnauba wax ; while colo- 
phony, shellac, sandarac, and mastic are readily soluble therein. 

Ether does not dissolve amber and shellac ; it makes copals 
swell, and partly but slowly dissolves carnauba wax ; it readily 
dissolves dammar, colophony, elemi, sandarac, and mastic. 

"Acetic acid does not dissolve amber and shellac ; it causes copal 
to swell ; it somewhat acts upon carnauba wax, but not at all upon 
any other of the resins above named. A hot solution of caustic 
soda, of sp. gr. 1.074, readily dissolves shellac, with difficulty 
colophony, and has no action upon the rest. In sulphide of car- 
bon, amber and shellac are insoluble ; copal swells therein ; 
elemi, sandarac, mastic, and carnauba wax are with difficulty 
dissolved, while dammar and colophony are readily so. Oil of 
turpentine has no action upon amber or shellac ; it causes copal 
to swell, and readily dissolves dammar, colophony, elemi, san- 
darac, carnauba, and very readily mastic. Sulphuric acid does 
not dissolve carnauba wax ; it dissolves and colors all other 
resins brown, except dammar, which becomes bright red. Nitric 



188 PRACTICAL TECHNOLOGY. 

acid does not act upon the resins, but covers carnauba wax 
straw-yellow, elemi dirty yellow, and mastic and sandarac 
bright brown. Ammonia does not dissolve some of these resins, 
but causes copal, sandarac, and mastic first to swell, afterward 
dissolving them ; colophony is easily soluble therein. 

KuBBER, Solvents for — These are ether (free from alcohol), 
chloroform, bisulphide of carbon, coal naphtha, and rectified oil of 
turpentine. By long boiling in water, rubber softens, swells, and 
becomes more soluble in its peculiar menstrua ; but when exposed 
to the air, it speedily resumes its pristine consistence and volume. 
Oil of turpentine dissolves caoutchouc only when the oil is very 
pure and with the application of heat ; the ordinary oil of turpen- 
tine of commerce causes india-rubber to swell rather than to be- 
come dissolved. In order to prevent the viscosity of the india- 
rubber when evaporated from its solution, one part of caoutchouc 
is worked up with two parts of turpentine into a thin paste, to 
which is added ^ part of a hot concentrated solution of sulphuret 
of potassium in water ; the yellow liquid formed leaves the 
caoutchouc perfectly elastic and without any viscosity. The solu- 
tions of caoutchouc in coal-tar, naphtha, and benzoline are most 
suited to unite pieces of caoutchouc, but the odor of the solvents 
is perceptible fcr a long time. Sulphide of carbon is the best sol- 
vent for caoutchouc. This solution, owing to the volatility of the 
menstrum, soon dries, leaving the latter in its natural state. 
When alcohol is mixed with sulphide of carbon, the latter does 
not any longer dissolve the caoutchouc, but simply softens it and 
renders it capable of being more readily vulcanized. Alcohol 
also precipitates solutions of caoutchouc. When caoutchouc is 
treated with hot naphtha distilled from native petroleum or coal- 
tar, it swells to 30 times its former bulk ; and if then tritu- 
rated with a pestle and pressed through a sieve, it aifords a ho- 
mogeneous varnish, the same that is used in preparing the patent 
water-proof cloth of Macintosh. Caoutchouc dissolves in the 
fixed oils, su(?h as linseed-oil, but the varnish has not the proper- 
ly of becoming concrete on exposure to the air. Cacjutchouc melts 
at a heat of about 256° or 260° after it has been melted ; it does 
not solidify on cooling, but forms a sticky mass which does not 
become solid even when exposed to the air for months. Owing to 
this property, it furnishes a valuable material for the lubrication 
of stop-cocks and joints intended to remain air-tight and yet be 
movable. 

Rubber, To cut. — Dip the knife-blade in a solution of caustic 
potash. 

Vinegar, Making, from alcohol (Artus's process). — Dissolve ^ 
oz. dry bichloride of platinum in 5 lbs. of alcohol. With this 
moisten 3 lbs. of charcoal broken to the size of a hazel-nut. Heat 
the charcoal in a covered crucible, and place it in the bottom of a 
vinegar- vat. This causes the rapid oxidation of the alcohol. 
Reheat the charcoal once in 5 weeks. 



THE FARM. 



FARM BUILDINGS. 



Beams, Fastening in walls. — The usual custom of building 
the ends of floor-timbers into brick and stone walls is apt, in case 
of fire, to throw over the walls ; and resting the tinibers on cor- 
bels interferes with the cornice-line below. By cutting the ends 
of the timbers on a bevel and laying in the wall, as in the annex- 




SETTING BEAMS IN WALLS. 

ed diagram, the cornice-line will not be broken ; and, in case of 
fire, the timbers will fall with little injury to the wall. 

Blasting. — In small blasts, 1 lb. of powder will loosen about 
4| tons of rock. In large blasts, 1 lb. of powder will loosen 2^ 
tons. 50 or 60 lbs. of powder inclosed in a bag and hung against 
a barrier will demolish any ordinary structure. One man can 
bore with a bit 1 in. in diameter, from 50 to 60 in. per day of 10 
hours in granite, or 300 to 400 in. per day in limestone. Two 
strikers and a holder can bore with a bit 2 in. in diameter 10 ft. 
per day in rock of medium hardness. 

Bricks from Gas-Coal Ashes.— These are of remarkable 
lightness, porosity, and dryness. The ashes, after being taken 
from the retorts, are spread on the surface of a clean floor ; they 
are then flnely pulverized, and 10 per cent of slaked lime, togeth- 
er with a small proportion of water, is intimately stirred and in- 
corporated with them. After a rest of 24 hours, the mixture is 
made into bricks by the ordinary process. The bricks are imme- 



190 THE FARM. 

diately transferred to tlie drying slieds, where a few days' expo- 
sure renders them fit for use. 

Brickwork, Preserving.— To exclude dampness, use the fol- 
lowing : f lb. mottled soap is dissolved in 1 gall, boiling water, 
and the hot solution spread steadily with a flat brush over 
the outer surface of the brickwork, care being taken that it 
does not lather ; this is allowed to dry for twenty-four hours, 
when a solution, formed of i lb. alum dissolved in 2 galls, 
water, is applied in a similar manner over the coating of soap. 
The soap and alum form an insoluble varnish, which the rain is 
unable to penetrate, and this cause of dampness is thus said to 
be effectually removed. The operation should be performed in 
dry, settled weather. 

Another method is to use 8 parts linseed oil andl part sulphur, 
heated together to 278°, in an iron vessel. 

Chimneys, Smoky, Causes of. — Want of sufficient height 
in the flue. The outlet of the chimney being placed in an 
exposed and cold situation, while the air with which the fire 
is supplied is drawn from a warmer and more sheltered re- 
gion. Excessive width in the flue, by which a large volume of 
cold air is drawn in and allowed to lower the temperature of the 
ascending column. Low temperature of the interior of the flue, 
in comparison with that of the external air. Humidity of the 
air. Too accurate fltting of the windows and doors, and joints in 
the flooring. The draft of one fire injuring that of others in the 
same house. A current caused by the heat of the fire circulating 
in the room. A flue of insufficient size. A foul flue. Displace- 
ment of masonry, or accumulation of mortar within the flue. 
The sudden obstruction of the draft, by gusts of wind entering 
the chimney-top. Increase of density of the air at the chimney- 
top, due to the effect of wind in chimneys rising from the eaves 
of roofs. Drafts within the room which throw the smoke out of 
the influence of the ascending chimney current. 

Chimneys, Smoky, Preventing effects of. — A screen or blower 
of wire gauze, from 36 to 40 wires to the inch, placed in front of 
range or stove flres, will prevent, it is said, smoke coming into 
the room when the chimney fails to draw well. 

Cistern, Building a. — One thing is essential, and is very ge- 
nerally neglected. It is to have the water as it comes into the 
cistern conducted to the bottom. In this way, the water is en- 
tirely changed when it rains. When the fresh water simply 
pours in at the top, it immediately runs off, and all the mass of 
stagnant water remains undisturbed, and soon becomes impure. 

Cistern Filter. — A wall of soft burned bricks is well adapt- 
ed for this purpose, when built up within the cistern. 

Concrete Foundations, To build. — The concrete is compos- 
ed of lime, sand, water, gravel, and round or broken stones. 
A trench of boards is first made, of the width of the desired foun- 
dation. Fill the trench witli the concrete to the depth of a foot 
or two, and let it stand until sufficiently hard ; then add another 
foot oi concrete, and so go on, adding concrete and raising trench- 
boards as the wall rises. 



THE FARM. 191 

Concrete Pavements. — The cheapest material for mixing 
with gravel is coal-tar from gas-works. 

Greenhouse, To build a cheap. — Mr. Peter Henderson says 
the ordinary span-roof is best. The walls are 4 ft, high, formed 
of locust or cedar posts. To the outside of these are nailed 
boards — rough hemloclv will do, if appearances are not consid- 
ered. To the boards is tacked the ordinary tarred paper used by 
roofers. Against the paper is again nailed the outer or weather 
boarding. This malies really a better wall for greenhouse pur- 
poses than an 8-inch one of brick, as we find that the extremes 
of temperature of the greenhouse — inside at 50°, and perhaps 10° 
below zero outside — very soon destroy an 8 -inch solid brick wall, 
particularly if exposed to the north or west. A wall of wood con- 
structed as above will last for twenty years, and be as good a pro- 
tection as one of 8-inch brick. The roof is formed by the ordina- 
ry sashes, 6 ft. in length by 3 ft. in width, which can be bought 
ready made. Heat with a fine not more than 60 and not less than 
30 ft. in length ; if more, the flue would not heat it enough, and 
if less it would be likely to get too much heat. About 50 ft. by 
11 is, we think, the best size of a greenhouse to heat with a flue. 
The flue should run all around the house — that is, it should start 
along under one bench, cross the end, and return under the other 
bench to the end where it begins, making the length of flue in a 
greenhouse of 50 feet about 110 feet lonof. It should have a 
'' rise " in this length from the furnace of at least 18 in., to se- 
cure a free draught. For the first 25 ft. of flue nearest the fur- 
nace it should be built of brick, forming an air-space inside of 
about 7 X 7 in. From this point (25 ft. from the fire) the flue 
should be formed of the ordinary drain-pipe cement or terra-cot- 
ta. The former is to be preferred, and that of 7 or 8 in. diame- 
ter is best. The cost of a greenhouse thus built in the vicinity 
of New- York, is about $6 per running foot — that is, one 50 ft. 
long by 11 ft. wide costs $300. 

ICE-HousE, To build an. — A house 12 ft. square by 8 or 9 ft. 
high is large enough for a good-sized family. It may be a frame 
building, entirely above the surface of the ground, and better if 
supported on posts, elevated a few inches, to be certain of good 
drainage. Build of joists, 2x3 in., with an outer boarding, hav- 
ing inside another series of uprights, also boarded, from 6 to 10 
in. removed from the outer shell, with a solid floor of plank, the 
space between the two walls filled with tan, sawdust, straw or 
chaff, and a roof of good pitch. A drain for Water should be 
made from the floor, and the space above the uprights, between a 
loose flooring and the pitch of the^ roof, filled with straw, hay, or 
some other dry, porous material. *0n the roof should be a venti- 
lator, the top defended from rain or snow. The ice should be 
packed in one solid mass, the sides not reaching the inner walls, 
but allowing a space of from 6 to 12 in. all around. The top of 
the ice should be covered with straw, and the door should be like 
the sides of the building, or double doors should be made, one in 
the outer and the other in the inner wall. Plant m.orning-glories 
or any other climbing plant about the building, and train them 
up over the roof, so that their foliage will serve as a protection 
against the sun. 



192 THE FARM. 

LiGHTNiNG-RODS, Valuable hints concerning. — Feather-beds 
are not a protection from lightning. The human body is a 
better conductor of electricity than feather-beds or other objects 
ordinarily contained in the apartments of dwellings, and there 
fore, when the lightning enters an apartment, the human body is 
likely to form one in a chain of inductions, determining the path 
of an electrical discharge, unless better conductors are in its vi- 
cinity to divert this action. 

The only place of absolute security in a thunder-storm is an iron 
building ; or next in safety is a building properly protected by 
lightning-rods. 

A copper rod of one inch in diameter, or an equal quantity of 
copper under any other form, will resist the effect of any discharge 
of lightning hitherto experienced. The copper rod is therefore 
the safest and best material that can be used, but it is expensive. 
Iron rods of one inch in diameter are very commonly used, and, 
if pointed with solid copper and properly put up, are efficacious 
in the great majority of cases. The particular form of the rod 
makes no difference. It may be round or square, twisted or hol- 
low, composed of one solid piece or made of wires twisted to- 
gether. It is the quantity of metal contained in the cross-section 
of the rod that is of value, not the form. 

Lightning-rods are provided with sharp points to allow the ac- 
cumulated negative fluid to pass off readily into the air and neu- 
tralize the positive fluid of the thunder-cloud. 

The object being to make so good a passage for the lightning 
to the ground as to remove all danger of its leaping to some con- 
ductor in the house, the greatest care must be taken not to have 
any break in the conductivity. As it is inconvenient to manufac- 
ture or transport the rods in one piece, the different parts must be 
in intimate connection when they are put up ; it is best to have 
them soldered, and the joints protected from the air and moisture. 

The point of the rod should be extended a little above the chim- 
ney or hioiiest part of the building, and should be fastened in 
ccmtact with the building by staples or cleats. Glass insulators 
should not be employed. It makes no difference in conductivity 
whether the rod is painted or not painted. 

No building can be said to be properly rodded or protected 
against lightning, unless the lower part of the rod or terminal 
under the ground is made quite extensive. The extremity of the 
rod should connect with masses of good conducting materials, 
such as old iroUj. or iron ore, or coke, or charcoal, laid intrenches, 
or the rod itself should be elongated, sunk deep in the ground, 
and carried a considerable distance from the building, and put in 
connection with water, or moi^ earth if possible. The golden 
rule for safety is : '' Provide the largest possible area of conduct- 
ing surface for the terminal of the rod." 

A lightning-rod which is not properly connected with the earth 
is quite dangerous. The very common method of merely stick- 
ing the lower end of the rod down into the dry earth near the 
surface of the ground is bad, and endano^ers the building, because 
dry earth is such a poor conductor, and the amount of rod surface 
in contact with the earth is so small. Under such conditions, a 
portion of the electric current will be likely to find an easier path 



THE FARM. 193 

to the earth, through the building than through the rod ; and a 
part of the electricity will therefore leave the rod, strike into the 
building, and down in various directions into the earth, making 
havoc as it goes. As a measure of prudence, house-owners should 
look to the terminals of their lightning-rods, and place there a 
considerable amount of the conducting materials above named. 

It was supposed to have been established by Charles and Gay 
Lussac that a lightning-rod protected an area whose radius was 
double the height of the rod extending above the building ; but 
this rule is no longer reliable, by reason of the extensive use of 
metals in the shape of pipes, etc., in the construction of the build- 
ings of our day. 

When electricity finds several paths to the ground, it will pre- 
fer the best, it is true ; but some portion will also pass along the 
poorer conductors If, therefore, any metallic substances lie 
within the area supposed to be protected, they are in danger of 
being struck. This is especially true where the lightning has a 
chance to jump to the gas and water pipes of a building. It is a 
good plan to connect these pipes with the lightning-rod ; if the 
rod is struck, the electricity will then have an excellent path into 
the ground, and will be rapidly diffused over the vast underground 
network of pipes. The danger to the inmates of the house of 
being struck from these pipes is less than that of receiving a 
shock from the powerful induced currents liable to be developed 
in tbem, if unconnected, during a thunder-storm. 

The more rods on a building the better, especially if all are 
connected with each other near their upper ends. 

Finally, in the way of general advice, we would say: Connect 
all your lightning-rods together, and also to your iron tank, and 
water, gas, or other pipes, not by separate connections, but so that 
there is some connection between all, which connection should be 
as high up as possible. If you have a metal roof, connect all rods 
with it. If the roof is not of metal, then connect your rods to- 
gether by means of a good-sized conductor funning along the 
ridge of the roof. Bear in mind that, to carry off the heaviest 
liglitning-flash known, a copper rod one inch in diameter is not 
considered too large ; and though of course such flashes are of 
very rare occurrence, they may come. Hence the great value of 
uniting your different rods high up. 

Mortar, Good weatherproof. — 3 bushels clean sand, mingled 
with ^ bushel good lime and i bushel cement, makes an excellent 
mortar which is not liable to be dislodged by storms. 

Mortar, To make.— The lime ought to be pure, completely 
free from carbonic acid, and in the state of a very fine powder ; 
the sand should be free from clay, partly in the state of fine sand 
and partly gravel ; the water should be pure, and, if previously 
saturated with lime, so much the better. The best proportions 
are 3 parts fine sand, 4 parts coarse sand, 1 part quicklime recent- 
ly slaked, and as little water as possible. There should always 
be enough water added at first ; if water is added after slaking 
has begun, it will be chilled and the mortar lumpy. The addition 
of burnt bones improves mortar by giving it tenacity, and ren- 
ders it less apt to crack in drying. 



194 THE FARM. 

Oak Timber, Seasoning. — Oak loses about ^ its weight in sea- 
soning, and about ^ its weight in becoming perfectly dry. 

Pavement, Farmyard. — Make a concrete of gravel or sand and 
Portland cement ; or easier, of gravel, sand, coal-ashes, and coal- 
tar. Dig away the earth for 5 in., lay a bottom of pebbles as 
large as goose-eggs, ramming well down. Sweep off clean, and 
pay the surface with hot coal-tar, thinly ; put on a coat of small- 
er gravel previously dipped in hot tar, drained, and rolled in coal- 
ashes with an intermixture of gravel. Roll it down as compact- 
ly as possible. Let the roller run slow, and let a boy follow it 
with a hoe to scrape all adherent gravel. Next, put on a coat of 
fine gravel or sand', coal-tar and some coal-ashes, to complete the 
surface. Roll again. This will take some weeks to harden, but 
will shed water, and eventually form a very firm surface. Do not 
use too much tar, but only enough to make the ingredients cohere 
under pressure. 

Rat-Proof Buildings. — The plan adopted in England is to 
have slate floors, sawed and planed to uniform sizes and thick- 
ness. The walls are also covered with sawed or planed slates, 
well jointed and secured to the wall or studding with screws, 
which makes each room as secure against rats as an iron or stone 
box would be. The slate used for the floor is from 1 to 3 in. thick, 
and that for the walls ^ in. thick. 

Rat-Proof Frame Buildings. — Nail strips of board to the 
sill between each flooring joist, on the inside, reaching to the un- 
der side of the flooring planks or boards, and thereby covering the 
shelf formed by the sill between the joists. The idea is to allow 
the rats no place to stand upon while they are cutting through 
the floor. 

Roads, Corduroy, To build. — First lay all small poles or 
brash transversely and across the road. Next take long trees— 
the smallest ends 'being at least 10 inches diameter — and place 
them longitudinally across the poles, in two rows, 8 feet apart 
from centre to centre, making the ends at the junction of each 
piece lap each other at least 3 feet, breaking joint on either side, 
and placing upon these ends large logs of sufficient length to ex- 
tejid across the road, and 2 feet on each side of these stringers. 
Cover the stringers with transverse logs, 12 feet long from scarf 
to scarf, and at least 10 inches in diameter at the smallest end, 
fitted close together on the straight portions ; the logs alternated 
with a large and small end, and on the outer side of curves, all 
the large ends, which will assist in the curvature of the road and 
the gravity of the vehicles. Next, adze off the centre ridges of 
these logs to a face of about 5 inches, for a width of 9 feet in the 
centre of the roadway, and cover this 9 feet with gravel, to fill in 
between the logs, and give a smooth surface. A good plan is to 
lay on the top of the road thus formed poles of 5 or 6 inches in 
diameter, spiked down on each side of the track, every 10 feet, 
with oak pins, to prevent, in frosty weather, the lateral sliding 
of wagons. 

Roofing, Pasteboard and asphalt. — This material is most 
suitable for flat roofs, having a fall of 1^ inches to 4^ inches per 



THE FARM. I95 

running foot. It may, however, also be used for roofs having a 
greater fall, the expense being in this case somewhat larger than 
lor flat roofs, as the laying on is more difficult. Cover the roof 
first with dry boards, f inch to 1 inch thick, and not above 6 inch- 
es broad ; if more than the last-named width, or if not saffi- 
cienily dry, the boards ought to be split once before being laid on, 
in order to keep them from warping, and every board should be 
fastened with three nails at least on each of the rafters. The 
boards do not require to be rabbeted ; only those ends of the 
boards which form the eaves, by extending beyond the wall need 
to be joined in the said manner. In case of boards f inch thick 
being applied, the rafters should not be more than 2 feet from 
each other, as the boards may be too elastic and not strong 
enough to support the weight of the workmen, while the roof 
will not be perfectly substantial. 

The roofing may be done either from gable to gable, or from 
the eaves to the foot -ridge, the first roll being laid with a bend 
of 1 inch beyond the roof, and fastened with the flat-headed iron 
wire nails supplied for that purpose. The second roll is laid 1| 
inches over the first, and so on till the roof is covered. The joints 
and heads of the nails are then coated with asphalt mastic, and 
the seams thus coated are strewed with dry sand. The whole 
roof is then coated with the mastic, and covered with sand. This 
coating, which is only to be effected in dry weather, renders the 
roof perfectly water-tight, and it can then, if desired, be painted 
or whitewashed. A hundredweight of mastic covers a surface of 
65 square yards. This process is in use in Copenhagen, Den- 
mark, and the roof weighs about ^ the weight of a tiled roof, and 
is substantial, resisting alike the influence of water, fire, heat, and 
cold. 

Roofing, Portland cement and tar. — The inclination of the 
framework of the roof (which must have an even surface) should 
be at the rate of from i to f inch per foot. The rafters or joists 
should not be more than 2 feet 3 inches apart, so as to give suffi- 
cient strength. As the rafters rest on the side walls, a compara- 
tively small quantity of timber is required. Boards of 1 inch or 
li inch thick are fastened or nailed on the rafters, and should be 
dovetailed. These are then covered with a layer of sand i or ^ 
inch thick, in order to produce an even surface. Strong brown 
paper, in continuous rolls, and as broad as possible, is then laid 
upon it, so that each length overlaps the other by about 4 inches. 
When the whole or a large part has thus been covered with pa- 
per, the mixture is put into a caldron, in the proportion of tar 100 
pounds to Portland cement 180 pounds. Care must be taken to 
heat the tar gently, and to mix the cement with it gradually, in 
order to prevent its boiling over. This mixture of tar and ce- 
ment must then be laid on as hot as possible on the paper with a 
tar-brush. The next layer of paper is then laid upon it, and 
smoothed with a light wooden roller. In this way the whole 
roof must be covered. In order to break the joints of the paper, 
begin the second layer with half the breadth, and proceed as be- 
fore. The third and fourth layers are laid in like manner, with 
alternate layers of cement and brown paper The last layer must 
be carefully covered with cement, and then strewn with sifted 



196 THE FARM. 

ashes to the thickness of J- inch. Next to the gutter is a board 
covered with zinc, and projecting about 2 inches. It should be 
laid on after the second layer has been completed, so as to be co- 
vered by the third and fourth. If there are any chimneys pro- 
jecting through the roof, they should be surrounded with zinc 
immediately after the first layer has been finished. 

Roofing Zinc. — Permit perfect freedom to the sheets. Confine 
them nowhere, and separate lengths of guttering, and any other 
portions of a roof requiring to be made in long pieces, as much as 
possible. Eaves-gutters should be made in short lengths, bent in 
the direction of the way in which the sheet has been rolled and 
soldered, the solder being put between the sheets, and one sheet 
lapping over the other. Nor must they be screwed to the rafters, 
as this is a practice which occasions a constant failure in the 
joints of the iron eaves-gutters. Wherever a down-pipe comes, 
there should be a stopped end in the gutter ; and the gutter 
should not be continued longer than possible in one place. Where 
it is lai-d behind a parapet, a separate piece of flashing will dis- 
connect it wholly from the sheeting on the roof. For guttering, 
the gauge used should be increased in proportion to lengtli ; 
there should be a proper substance in all cases. Oak boarding 
will spoil the zinc, and the fir boarding should be dry — the 
boards with an aperture of about ^ inch between each. If they 
are damp, as much oxidation will take place on the under side of 
the zinc as on top of it. From experiment, it appears that the 
oxidation proceeds for about four years, gradually diminishing 
after the first three months, when it hardens into a protecting 
coat of a dark gray color, preserving the metal beneath from fur- 
ther deterioration. A sheet of zinc exposed to the atmosphere for 
a series of years loses little or nothing of its weight or thick- 
ness, and its surface remains hard and polished as enamel. 

Shingles, To prevent decay of. — Put into a lar^^e tub 1 bar- 
rel of wood-ashes lye, 5 pounds white vitriol, 5 pounds alum, and 
as much salt as will dissolve in the mixture. Make the liquor 
quite warm, and put in as many shingles at a time as it will co- 
ver. When one batch of shingles is well soaked, remove and 
put in another. Then lay the shingles in the usual manner. 
With the liquor that is left, mix enough lime to make white- 
wash, and color with lampblack, ochre, or Spanish brown. Ap- 
ply to the roof with a brush or old broom. This wash may be 
renewed from time to time. 

Shingles, Painting. — Lay low-priced shingles — say from $2.75 
to $4 per thousand — and paint them with a coat of tar and 
asphaltum — say one barrel coal-tar, costing $'S ; ten pounds of 
asphaltum at 3 cents, 80 cents ; ten pounds ground slate, at 1 
cent, 10 cents ; two gallons dead oil at 25 cents, 50 cents, which 
should be added after the other has been wetted and thoroughly 
mixed. This mixture is as good as any thing that can be put on 
to shingles, as it will thoroughly keep the water out ; and, if 
dry, they will not rot under the lap, nor will the nails rust. 

Slates, Roofing, Selection of. — Dark purple and green slates 
are the best for roofing ; others are liable to fade unequally, and 
produce a disagreeable appearance. 



THE FAKM. 



197 



Sled-Body, To build a transverse. — Make tke sills out of 
1-incli or f-incli boards, with cross-pieces of the same thickness 
bolted between the sills, which are double. You can make these 
very light and limber. Now put on your side-boards with a bolt 
down through the rave and sill, which will make it very 
stiff, and can be made very light, and with all the strength 
j)Ossible. 

Smoke-House, Cheap and good. — For 50 hams, make dimen- 
sions 7x8 feet. Dig all the ground out to below the frost line, 
and fill up to the surface with small stones. On this lay a brick 
floor with lime mortar. Walls of brick, 8 inches thick by 7 feet 
high, and a door on one side, 2 feet wide. Door of wood, lined 
within with sheet-iron. For the top, put on joists, 2x4, set up 
edgewise, and 8^ inches from centre to centre, covered with brick 
and with a heavy coat of mortar. Build a small chimney over 
the centre, arching it over and covering it with a single roof in 
the usual way. An arch should be built on the outside, with a 
small iron door, similar to a stove-door, to shut it up. Make a 
hole in the arch through the wall of the house, and put an iron 
grate over it. The arch is much more convenient to put the fire 
in, than to build the fire inside the house, and the chimney 
causes a good draught through the latter. Burn good corn-cobs 
or hickory wood. This house should cost about $20. 

Stables, Building. — Bricks, built in hollow walls, are better 
than any other material. Commence with a stone foundation — 
the bottom course of which is broader than the stone-work above 
it — laid in half cement mortar up to the grade line, and then build 
the biick wall upon that, filling in all the space inclosed by the 
walls with concrete up to the line of the top of the water-table. 
Then pave with stones, firmly bedded to form a floor. On the 
outside, there should be a stone water-table, 8 or 10 inches high, 
projecting 1 or 2 inches outside of the main walls above, and 
having the upper surface of the projection beveled off to shed the 
water. Just above the water- table, it is well to have a course of 
slate built in the full thickness of the walls, which will prevent 
any dampness rising up into them from the ground by capillary 
attraction. Above the water-table, the walls should be built up 
with a smooth face, and with close, neatly struck joints inside as 
well as out, so as to present a clean, even surface, which should 
always be kept painted or washed with a lime or cement wash. 
Above the wall-plate, the space should be filled in to the under 
side of the root-boards. The ceilings over the main story should 
be lathed and plastered ; partly for the sake of the neat appear- 
ance, partly to keep away cobwebs which infest exposed beams, 
and partly to prevent foul air rising from the room below, and 
tainting the hay-loft. The doors and windows inside should be 
trimmed with architraves, even if the latter be merely strips of 
the cheapest stuff. It may be desirable to fur out and lath and 
plaster the walls of a stable ; bat if this is to be done, it is. better 
to wainscot with wood up to the height of, say 5 feet, and to fill 
in the space between the walls and the wainscot, as high as prac- 
ticable, with broken glass and mortar, and then to lath and plas- 
ter from the wainscot tip to the ceiling. A wooden stable, too. 



198 THE FAKM. 

may with advantage be treated in the same way, but the space 
behind the wainscot being wider, may be packed with bricks and 
mortar, and made solid in that way. 

Timber, Strength of. — The strongest side is that which in its 
natural position faced the north. 

Timber, To test tlie soundness of. — Apply the ear to the mid- 
dle of one of the ends, while another person strikes upon the op- 
posite extremity. If the wood is sound and of good quality, the 
blow is very distinctly heard, however long the beam may be. If 
the wood is disaggregated by decay or otherwise, the sound will 
be for the most part destroyed. 

Trough, To make a tight. — Joint up the plank, and then, with 
a wide punch, set down a groove about -f^ in. deep the whole 
length ; then take off two or three shavings more, and put the 
trough together. When the wet gets into that joint the groove 
swells out again just the thickness it was at first, and of course 
two or three shavings thicker than the plank, and so closes all 
up tight. Wood can also be ornamented by punching down 
carefully in patterns, planing off a little, and then wetting ; the 
parts punched down show in relief above the planed surface, and 
make quite a puzzle. 

Water-Closet, To put up a. — The engraving represents 
sectional views of the water-closet in the upper floor of a 
two-story house. A A is the level of the surface of the ground at 
the back court and of the kitchen floor. B is a 6-inch vitrified 
fire-clay siphon-trap, with an open iron grating, C, at its top, 
which grating maybe hinged. D is 4 inch soil-pipe from the 
water-closet ; it is here shown coming down inside the wall ; 
in other cases it may be carried down the outside. One advan- 
tage of such pipes being carried down the inside is that they are 
more likely to be protected from frost. F is a ^-inch or 2 -inch 
lead pipe lor ventilating the soil-pipe. In this case, it is carried 
through the wall ; in other cases it may be carried up through 
the roof. G is the water-closet trunk, made of iron, it being a 
pan water-closet which is here shown. H is a f-inch lead pipe, 
carried through the wall, and put in to ventilate the trunk, or 
that space between the water in the pan, I, or basin, J, and the 
water in the siphon-trap, E. This f-inch ventilating pipe, H, is 
a very important one, and its use ought to be the rule in place 
of the exception, as is at present the case. It works as follows : 
When the handle of the water-closet is lifted, then any foul air 
lying in the trunk, in place of coming out into the apartment, is 
sent outside with a rush through this pipe, H ; besides, being open 
to the air, it tends to prevent the accumulation of such foul air 
in the trunk. 

In order to keep the outer orifices of the pipes, F and H, al- 
ways open, it is a good plan to solder on one or two pieces of 
copper wire across them. J is the water-closet basin, and the two 
small circles shown, underneath K K, are the india-rubber pipes. 
A 3-inch zinc ventilating pipe may be carried up through the 
roof to ventilate the space or inclosure in which the water-closet 
is situated. A gas-bracket placed right below it will help, when 
lighted, to cause an upward current. The empty space at N is 



THE FAKM. 



199 




BUILDING WATER-CLOSETS. 

supposed to be the water-closet window. O is the surface of the 
floor of the upper flat. No gas can accumulate in the soil-pipe, 
for the pressure of the atmosphere on the surface of the open 
grating, C, tends to send a current of fresh air through the soil- 
pipe and out at the ventilating pipe, F. 

Water-Gate, a good. — This is an excellent device for fencing 
purposes over small streams. A gate, sliding in upright ways at 
the ends, like an old turnpike gate, has attached to the bottom 
board (a scantling is better, as not so likely to be broken in hi^h 
water) crutches which rest upon empty barrels or casks. The up- 
rights at the ends of the gate are provided with friction-rollers, 
so that the gate slides up and down easily in the ways. Two or 
three casks will generally support the weio-ht of the gate, so that 
it descends nearly to the surface of, but does not enter, the water. 
A gate thus constructed will rise and fall with the stream, and 
is not liable to be washed away at high water. 

Whitewash, for outside work. — Take quicklime, ^ bushel ; 
slake, and add common salt, 1 pound : sulphate of zinc. ^ 
pound ; sweet milk, 1 gallon. Dissolve salt and zinc before add- 
ing, and mix the whole to proper consistence with water. 



200 'i'^^ farm:. 

Wooden Buildings, To frame. — Particular attention should 
be paid to binding the top of the walls well together. This is 
accomplished by framing the wall-plate all around the house, 
and spiking the ceiling joists down on the same ; then herring- 
bone, bridging these joists in as many rows as are necessary to 
make a thoroughly stiff brace for the whole. The roof (no mat- 
ter whether Uothic or Mansard) can not exercise any bad influ- 
ence in pushing out the walls, when this system is adopted. 

Wood, To season and prevent warping.— Strip off bark, and 
bury about one foot deep in the spring, leaving in the ground for 
six months, and you will find no difficulty. This was the only 
way by which the sapadillo or mountain mahogany in the Sierra 
Nevada could be seasoned, it being one of the hardest and most 
brittle kinds of wood known. 

Windmill, To build a. — Windmills can be either horizontal 
or vertical, but the latter are almost exclusively^ employed. In 
the vertical windmill, the shaft is inclined to the horizon at au 
angle of from 5° to 15°, when the wheel is placed at the top of a 
tower ; so that the wheel will clear the sides of the building, 
and allow space for the action of the wind. If the wheel is 
supported by a post, the shaft may be horizontal. The connec- 
tion of the shaft with the pump or other mechanism may be 
made either with gearing or by means of a crank and connecting 
rod. The shaft must be free to swing around in any direction, 
so that the wheel can always face the wind. It is moved, in the 
case of small windmills, by the use of a' weather-vane on the 
end of the shaft opposite to the wheel. With large windmills 
supported on towers, the top of the tower is generally arranged 
so that it can be rotated, and a small auxiliary wind- wheel, con- 
nected by gearing, moves it into the proper position as the direc- 
tion of the wind changes. The wheel of a windmill may be 
covered with cloth, or with slats of wood or metal, the cover in 
either case being technically known as the sail. 

Make the sail of a series of joined slats, that present a close 
surface to wind of the ordinary velocity, and open, thereby de- 
creasing the surface, as the velocity of the wind increases. The 
best velocity for a windmill is such that its periphery moves 
about 2f times as fast as the wind. Thus, if the wind is moving 
at the rate of 20 feet a second, the tips of the sails should move 
at the rate of 52 feet a second, so that, if the wheel were 12 feet 
in diameter, it should make about 88 revolutions a minute. Of 
course, if the velocity of the wind varies greatly, it will be 
impossible to keep the speed constant, so that windmills are not 
ordinarily well suited for work requiring steady motion ; although 
they answer very well for moving pumps, if an intermittent 
supply of power is not a serious obstacle. In some sections, 
however, the prevailing winds are quite steady, and in such 
cases windmills can be applied with advantage to grist-mills 
and other useful work. The force and velocity of the wind can 
only be determined by experiment, but the results of previous 
experimenters may be useful : 







THE FAKM. 


201 


Velocity of wind. 










Perpendicular 




In feet per 


In miles 


force, in pounds 


Common expressions of 


second. 


per hour. 


per square foot. 


the force of the wind. 


10 


6.82 


0.33 


Gentle pleasant wind. 


20 


13.64 


0.91 


Brisk gale. 


30 


20.56 


2.04 


Very brisk. 


40 


27.27 


3.92 


High wind. ' 


50 


34.09 


6.25 


Very high. 


60 


40.91 


9.25 


Very high. 


70 


47.73 


12.75 


A storm. 


80 


54.55 


16.34 


A storm. 


90 


61.36 


20.74) 

25.28 ^ 




100 


68.18 


A great storm. 


110 


75.02 


30.89) 




120 


81.84 


36.75 


A hurricane. 


180 


88.65 


43.26 


A hurricane. 


140 


95.47 


50.32 


A violent hurricane. 


150 


102.29 


57.56 


A violent hurricane. 



In the accompanying figure is shown one of the four sails of a 
windmill, it having been found that four sails of proper propor- 
tion produce the best effect. The 
piece P B is called the whip of the 
sail ; C D, E F, G H, etc., the bars 
of the sail. The bars are inclined 
to the plane of revolution at differ- 
ent angles, the angle made by any 
part of the sail with this plane be- 
ing called the weather of the sail. 
Making the distances A O, N L, LI, 
etc., each equal to ^V of flie diame- 
ter of the wheel, the best values for 
the angle of weather are as follows: 



For N 0-18° 
For L M— 19° 
For J K— 18° 



For G H— 16° 
For E F— 12i= 
For C D— 7° 



The sail stretched over these bars 
will be a warped surface, some- 
what resembling the blade of a 
screw-propeller. The part B D 0, 
called the leading sail, is triangular, 
and B D is tV of the diameter of the 
wheel, B C being -^, and C N ^^ of 
the diameter. The main body of 
the sail, B C N O, is commonly rect- 
angular. A windmill of the best 
proportions, running under the most 
favorable circumstances, utilizes 
about -fo~o of the energy of the 
wind that acts on an area equal to a circle having the same 
diameter as the wheel. It would not be advisable to count 
on realizing more than half this power in general practice ; and 
on this assumption, we have the following empirical rule for 




BUILDING A WINDMILL. 



202 THE FAEM. 

determining the diameter of a wheel to give a certain amount 
of power with an assumed velocity of the wind : 

Divide the required horse-power by the cube of the velocity 
of the wind in feet per second ; take the square root of the 
quotient and multiply it by the number 2024.8. The product 
will be the required diameter in feet. Example : A windmill is 
to be erected in a locality where the general velocity of the wind 
is about 20 feet per second. It is to be attached to a pump, the 
work required of it being to raise 1000 gallons of water per 
hour throucrh a heio^ht of 20 feet 1000 United States gallons of 
water weigh about 8320 pounds, and, taking into effect the re- 
sistance of the pump, the power required will be about ^ of a 
horse-power, or 0.167 horse-power. Dividing this by 8000, the 
cube of the velocity of the wind, extracting the square root, and 
multiplying by 2024.8, we obtain 9 J ft. as the required diameter of 
the wheel. Referring to the figure, we find that, in this case, 
C N is 8 feet lOJ inches, B D, 7f inches, and B C, 11-3% inches. 
The velocity of the tips of the sales should be 52 feet per second, 
or the wheel should make about 108 revolutions a minute. 



THE DAIRY. 

Butter, Philadelphia. — The pans containing milk to the 
depth of 8 inches are set in fiowin^ water, so as to be maintained 
at a temperature of about 58° Fahr. After standing 24 hours, the 
milk is skimmed, and the cream put in deep vessels of a capacity 
of about 12 gallons. It is kept at a temperature of 58° to 59° until 
it acquires a slightly acid taste, when it goes to the churn. The 
churn is a barrel revolving on a journal in each head, and is 
driven by horse-power. The churning occupies about an hour ; 
and after the buttermilk is drawn off, cold water is added and a 
few turns given to the churn. The water is then drawn off. This 
is repeated until the water as it is drawn off is nearly free from 
milkiness. The butter is worked with butter-workers, a damp- 
ened cloth meanwhile being pressed upon it to absorb the 
moisture and free it of buttermilk. The cloth is frequently 
dipped in cold water, and wrung dry during the process of 
wiping the butter. It is next salted at the rate of 1 ounce salt 
to 8 pounds butter, thoroughly and evenly incorporated by means 
of a butter- worker. It is then removed to a table, where it is 
weighed out and put into pound prints. After this, it goes into 
large tin trays, and is set in the water to harden, remaining 
until next morning, when it is wrapped in damp cloths and 
placed upon shelves, one above another, in tin-lined cedar tubs, 
with ice in the compartments at the ends ; and then it goes 
immediately to market. A Philadelphia butter dealer says that, 
for the best butter, the cows are fed on white clover and early 
mown meadow hay, cut fine and mixed in with corn meal and 
wheaten shorts. No roots are fed, except carrots. 



THE FARM. 



20S 



Churning Milk, Temperature for. — 60° Fahr. 

Cream- Gauge. — In a can 20 in. deep and 8 in. in diameter, cut 
a slot a few inches long. In this slot, insert a strip of glass, in 
grooves, and cement with white lead. Graduate the tin next to 
the glass. Set the milk in the can, and allow the cream to rise. 
The percentage may be seen on the glass and noted by the 
scale. 

Cream, White specks in. — These are caused by too much acid 
in the cream. Cream should never stand in a room where the 
milk is set, but should be put into a cool place if you would 
avoid specks. 

Cows, Care of. — Milk coming from ill-nourished, half- fed cows, 
having no surplus of food beyond minimum requirements of na- 
ture, is injurious, and may be a source of disease. Cows deprived 
of an abundance of good water, ventilation, and exercise, secrete 
impure and dangerous milk, which may be loaded with ^ases, 
animalculge and fever-germs. The milk from old, debilitated 
cows fed on grains or overstimulating food, is also imperfect and 
unhealthy to a variable degree. The nervous condition of the 
cow at the time of milking determines the purity of the milk. 
If this is neglected, the milk is an active source of disease, and 
is positively dangerous and fatal. 

Cow-Stables, Ventilation of. — Lay the floor of the stable upon 
a solid bed of earth and gravel, with a fall of 6 in. in 12 ft. from 
the stanchions, with the same ratio of descent, to a point for outlet 
of liquids. Make a platform raised 6 in. for the cows to stand or 
lie upon. The floor and platform plank should be bedded in 
water-lime mortar, so that there shall be no soaking down nor 
hiding-place for stale urine to deposit and generate venomous 
odors. 

Milk, Poisonous sour. — Sour milk, after protracted exposure 
to the sun, develops a poisonous quality, sufficient to cause dis- 
ease and death to pigs fed thereon. 

Milk, Setting. — Place the pans in cold water, which will pro- 
tect the milk from the acid until the cream has time to rise. 
For cream to rise readily on milk, set in cold water ; the atmo- 
sphere in the room should be warmer than the water. There 
will as much cream rise on milk set in cold water in one hour 
as there will on milk not set in water in 24 hours. 

Milk, Tainted. — Never allow dead animals to decay about a 
pasture, or any where near a barn or other localities inhabited 
by the milch-cows. The carrion odor is sure to affect the milk. 

Milk, Testing for cream. — A simple method of determining 
the quantity of cream in any sample of milk consists in agitating 
the milk in a graduated glass tube with its bulk of ether for 4 
or 5 minutes. Add alcohol in volume equal to that of the milk, 
and shake for 5 minutes. Place the tube vertically and allow it 
to rest for a brief period, when the oily matter will rise to the 
surface so that its amount may be read off on the scale and the 
percentage easily computed. 

Milk, To insure good. — The following questions Mr. X. A. 



204 THE FARM, 



Willard, a well-known dairy authority, recommends to be writ- 
ten out and posted about the dairy : " Do your cows feed in 
swamps and on boggy lands ? Have you good, sweet running 
water convenient for stock, and is it abundant and permanent in 
hot, dry weather? Have you shade-trees in your pasture, or 
do you think that cows make better milk while lying down to 
rest in discomfort in the hot sun ? Do you use dogs and stones 
to hurry the cows from pasture at milking time, thus overheat- 
ing their blood and bruising their udders ? Do you cleanse the 
udders of cows before milking by washing their teats with their 
own milk, and practice further economy by allowing their drip- 
pings to oro into the milk-pail ? Do you enjoin your milkers to 
wash their hands thoroughly before sitting down to milk ? When 
a cow makes a misstep while being milked, do you allow your 
milkers to kick her with heavy boots, or to pound her over the 
back and sides with a heavy stool ? Is the air about your ' milk- 
barn' or milk-house reeking with the foul emanations of the 
pig-sty, the manure-heap, or other pestiferous odors ?" 

Milk, To prevent souring by thunder-storms. — A fire started 
in the dairy is an excellent preventive. This should be done 
even in the hottest weather. The object is to remove the damp, 
moist, heavy air, which is injurious to the milk. 

Milk, To remove taste of turnips in. — Give the cow no turnips 
for two or three hours before milkino-. It is better to feed only 
the centre of the turnip, cutting off the top and bottom. A 
tablespoonful of nitre dissolved in as much water as it will take 
to a gallon of milk, placed in the pail before milking, is said to 
remove the taste of the vegetable. 



FARM HINTS AND RECIPES. 

Bee Moths, To kill. — Bee moths can easily be killed in large 
numbers by setting a pan of grease, in which is a floating ignited 
wick, near the hives after dark. The moths will fly into the light 
and fall into the grease. 

Bones, Reducing. — Place them in a large kettle filled with 
ashes, and about one peck of lime to a barrel of bones. Cover 
with water and boil. In 24 hours all the bones, with the excep- 
tion, perhaps, of the hard shin-bones, will become so much soft- 
ened as to be easily ]3ulverizt'd by hand. They will not be in 
particles of bone, but in a pasty condition, and in an excellent 
form to mix with muck, loam, or ashes. By boiling the shin- 
bones 10 or 12 hours longer, they will also become soft. 

Bones. Value of, as a fertilizer.— 100 lbs. of dry bone-dust 
add to tlie soil as much organic animal matter as 300 lbs. of 
blood or flesh, and also at the same time 5 iheir weight of inorganic 
matter— lime, magnesia, common salt, soda, and phosphoric acid. 
Superphosphate of lime, commonly used by farmers, is simply 



THE FARM. 205 

bones treated with. ^ their weiglit sulpliuric acid and an equal 
quantity of water. 

Carbonic Acid GtAS, Removing from wells, cisterns, etc. — (1.) 
A bellows with a rubber hose reaching near the bottom will soon 
blow out the gas. (2 ) Let down a large bucket, draw up and 
empty tlie gas as if it were water. (3.) Pour down water ; do this 
when a person falls to the bottom from inhaling the gas. (4.) 
Let down an umbrella spread, and pull up quickly several times 
in succession. 

Caterpillars, Exterminating. — Orchard or tent caterpillars 
leave their rings of eggs on the young twigs. If these are cut off 
with a clipping pole, it will prevent in every instance a large 
nest of caterpillars, and be much more easily done than after the 
latter have grown. 

Caterpillars, Remedy for. — A solution (1 part in 500) of sul- 
phide of potassium, sprinkled on the tree by means of a hand-sy- 
ringe, is extensively used in France. 

Celery, Propagation of. — A deep trench should first be dug, 
at the bottom of which a layer of sticks of wood, say 6 in. thick, 
should be placed, a drain-pipe being placed endwise upon one or 
both ends of the layer. The sticks should be then covered with 
about a foot of rich mould, wherein the plants should be set in a 
row, and about 5 in. apart. The plants should be well watered, 
the water being supplied through the drain-pipes, so that, pass- 
ing through the layer of sticks, which serves as a conduit, the wa- 
ter is supplied to the roots of the plants. In earthing up, care 
should be exercised to close the stems of the plant well together 
with the hand, so that no mould can get between them. The 
earthing process should be performed sufficiently frequently to 
keep the mould nearly level with the leaves of the outside stems. 
If these directions are carefully observed, the plant may be grown 
at least 4 ft. in length, and this without impairing the flavor. 

Charcoal, Effect of, on flowers. — All red flowers are 
greatly benefited by covering the earth in their pots with about 
an inch of pulverized charcoal. The colors (both red and violet) 
are rendered extremely brilliant. Yellow flowers are not affected 
in any way by charcoal. 

Chickens, To fatten. — The best food for this purpose is Indian 
meal -and milk. 

Chinch-Bugs, To destroy. — Put old pieces of rag or carpet in 
the crotches of the trees attacked. When the worms spin, as they 
will, in the rags, throw the latter in scalding water. The bugs 
can thus be killed by wholesale. 

Cider Barrels, To clean. — Pour in lime-water, and then in- 
sert a trace-chain through the bung-hole, remembering to fasten 
a strong cord on the chain so as to pull it out aorain. Shake 
the barrel until all the mould inside is rubbed off. Rinse with wa- 
ter, and finally pour in a little whisky. 

Cider Casks, To prepare. — Cider should never be put into new 
casks without previously scalding them with water containing 
salt, or with water in which apple-pomace has been boiled. Beer- 



206 THE FARM. 



casks sliould never be used for cider, nor cider-casks for beer. 
Wine and brandy casks will keep cider well, if the tartar adher- 
ing to their sides is first carefully scraped off and the casks be 
well scalded. Burning a little sulphur in a cask will effectually 
remove must. 

Cider from apple-parings. — The parings of a bushel of apples 
will yield 1 qt. of cider by the aid of the hand-press. 

Cider-Making, Hints for. — 1. No good cider can be made from 
unripe fruit. The nearer to perfect ripeness the apples, the bet- 
ter the cider. 2. No rotten apples, nor bitter leaves, nor stems, 
nor filth of any kind should be ground for cider. 3. Two presses 
are really necessary for each mill, so that the pomace can be ex- 
posed to the air in the one, while it is being pressed in the other, 
and thus acquire a deeper color. 4. New oak barrels, or those in 
which whisky or alcohol has been kept, are the best. 5. If more 
color and richer body are desired, a quart or two of boiled cider 
to each barrel will impart them. 

Cider, Purifying. — Cider may be purified by isinglass, about 
1 oz. of the latter to the gallon. Dissolve in warm water, stir 
gently into the cider, let it settle, and draw off the liquor. 

Cider, To preserve sweet for years. — Put it up in air-tight cans, 
after the manner of fruit. Rack it off the dregs, and can before 
fermentation sets in. 

Coal- Ashes as a fertilizer. — Mix them with a small propor- 
tion of well-rotted horse-manure, sifting the ashes first, and you 
will have an excellent fertilizer. 

CoRN-CoBS, Utilization of. — Save the corn-cobs for kindlings, es- 
pecially if wood is not going to be plentiful next, winter. To pre- 
pare them, melt together 60 parts resin and 40 parts tar. Dip in 
the cobs, and dry on sheet-metal heated to about the temperature 
of boiling water. 

Dogs, Bed for. — The best is newly made deal shavings. They 
will clean the dog as well as water, and will drive away fleas. 

Dust, Road, Value of. — During a dry season, every country 
resident should secure several barrels of road-dust. Those who 
keep poultry may secure by its use a valuable fertilizer, nearly as 
strong as guano, with none of its disagreeable odor. Place an 
inch or two of road-dust in the bottom of a barrel ; then, as the 
poultry house is regularly cleaned, deposit a layer an inch thick 
of the cleanings, and so on, alternately layers of each till the bar- 
rel is full . The thinner each layer is, the more perfect will be 
the intermixture of the ingredients. If the soil of which the 
road-dust is made is clayey, the layers of each may be of equal 
thickness ; if sandy, the dust should be at least twice as thick as 
the layer of droppings. Old barrels of any kind may be used for 
this purpose, but if previously soaked with crude petroleum or 
coated with gas-tar, they will last many years. If the contents 
are pounded on a floor into fine powder before applying, the fer- 
tilizer may be sown from a drill. Road-dust is one of the most 
perfect deodorizers of vaults — converting their contents also into 
rich manure. Place a barrel or box of it in the closet, with a 



THE FARM. 207 

small dipper, and throw down a pint into the vault each time it 
is occupied, and there will be no offensive odor whatever. This 
is simpler, cheaper, and better than a water-closet, and never 
freezes or gets out of order. Mixing the road-dust with equal 
bulk of coal-ashes is an improvement, making the fertilizer more 
friable. 

Fertilizer, A cheap. — This consists of sulphate of ammonia, 
60 lbs. ; nitrate of soda, 40 lbs. ; ground bone, 250 lbs. ; plaster, 
250 lbs. ; salt, ^ bushel ; wood ashes, 3 bushels ; stable manure, 
20 bushels. Apply the above amount to six acres. Labor in pre- 
paring included, it costs about $15. It is said to give as good 
results as most of the commercial fertilizers costing $50 per ton. 

Fish- Net, To preserve from decay. — Steep in melted paraffine. 

Fowls, Fattening. — It is said that charcoal will fatten fowls, 
and at the same time give the meat improved tenderness and 
flavor. Pulverize and mix with the food. A turkey requires 
about a gill a day. 

Fruit, To preserve. — Fruit is kept in Russia by being packed 
in creosotized lime. The lime is slaked in water in which a little 
creosote has been dissolved, and is allowed to fall to powder. 
The latter is spread over the bottom of a deal box, to about one 
inch in thickness. A sheet of paper is laid above, and then the 
fruit. Over the fruit is another sheet of paper, then more lime, 
and so on, until the box is full, when a little finely powdered 
charcoal is packed in the corners, and the lid tightly closed. 
Fruit thus inclosed will, it is said, remain good for a year. 

Geese and Ganders, To distinguish. — The goose has always 
a feminine appearance and the gander a masculine. Her head is 
smaller and her beak shorter ; knot on forehead smaller and not 
so pointed ; her neck shorter and more delicate ; the black streak 
on back of neck not so high ; colored ring around head not so 
bright ; her neck comes out of her body more abruptly (this is 
occasioned by her having a larger breast than the gander), giving 
a square appearance to the body. The voice of the gander is 
keener and louder ; coloring about head more brilliant ; eyes 
keener and always on the lookout. 

Grafting Wax. — Take beeswax 1 part, resin 1 part, with 
enough tallow to soften. Melt all the ingredients together. 

Grafts, Cutting and storing. — There is no better time to cut 
grafts, than at the commencement of winter. In cutting and 
packing them away, let them be labeled. For this purpose they 
should be tied up in bunches, not over 2 or 3 inches in diameter, 
with 3 bands around each bunch— at the ends and middle. The 
names may be written on a strip of pine-board or lath, ^ in. 
wide, i\) in. thick, and nearly as long as the scions. This, if 
tied up with the bunch, will keep the same secure. For conveni- 
ence in quickly determining the name, there should be another 
strip of lath, sharp at one end, and with the name distinctly 
written on the other, thrnst into the bundle with the name pro- 
jecting from it. If these bunches or bundles are now placed on 
end in a box, with plenty of damp moss between them and over 
the top, they will keep in a cellar in good condition, and any sort 



208 THE FARM 

may be selected, and withdrawn without disturbing the rest, by 
reading the projecting label. It is needful, however, to keep an 
occasional eye to them, to see that the proper degree of moisture 
is maintained — which should be just enough to keep them from 
shriveling, and no more. 

Grapes, To ripen.— In the Rhine district, grape-vines are kept 
low and as near the soil as possible, so that the heat of the sun 
may be reflected back upon them from the ground ; and the 
ripening is thus carried on through the night by the heat radiated 
from the earth. 

Grasshoppers, To utilize. — The grasshoppers, desiccated and 
ground, are useful as a fertilizer ; but in this prepared condition, 
they form an excellent food for all insect-feeding birds. There is 
no better food for all young domestic fowls. Containing silicic 
acid in a soluble state, they seem specially adapted for young 
birds, promoting the growth of feathers. 

Grassing a Slope. — A steep slope may be grassed over with- 
out sodding by first smoothing the surface and then mixing a 
tough paste or mortar of clay, loam, and horse-manure, with suffi- 
cient water. The grass seed, which should be a mixture of Ken- 
tucky blue grass and white clover, should be thickly but evenly 
scattered upon the moist surface of this plaster as it is spread 
upon the bank. Tlie plaster should be at least one or two inches 
thick, and a thin layer should be laid over the seed. The surface 
should be kept moist, and a light dressing of some active ferti- 
lizer would help the growth. In a few weeks the growing grass 
should be cut, and should be kept short at all times until a thick 
sod is formed. . 

Guano, Handling. — Many cases of poisoning have occurred by 
contact of guano with wounds. It should be handled with gloved 
hands. 

Guano, Home-made. — Make a compound of 1 bushel ashes, 2 
bushes fowl-manure, 1^ bushels plaster, and 4 bushels muck. 
Spread the muck on the barn-floor and dump the fowl-manure on 
top of it. Pulverize the latter with the spade, and mix in the 
other ingredients. Moisten the heap with water, or, better, with 
urine, before planting. Deposit about a handful in each hill of 
corn, potatoes, or beans, mixing it with the soil before putting in 
the seed. 

Harness, Cleaning. — Unbuckle all the parts and wash clean 
with soft water, soap, and a brush. A little turpentine or benzine 
will take off any gummy substance which the soap fails to re- 
move. Then warm the leather, and, as soon as dry on the sur- 
face, apply the oil with a paint-brush or a swab. Neat's-foot oil 
is the best. Hang up the harness in a warm place to dry, but do 
not let it burn. 

Harness, Oiling. — Give one or two coats of lampblack and 
castor-oil warmed sufficiently to make it penetrate the stock 
readily. Then sponge the harness with 2 qts. warm soap-suds ; 
when dry, rub over a mixture of oil and tallow, equal parts, with 
enough Prussian blue to give color. When well rubbed in, this 
compound leaves a smooth, clean surface. 



THE FARM. 209 

Harness, Working* team. — Do not use martingales on working 
teams. See that the hames are buckled tight enough at the top 
to bring the draft-iron near the centre of the collar. If too low, 
it not only interferes with the action of the shoulder, but gires 
the collar an uneven bearing. 

Hay, Spontaneous combustion of. — Hay, when piled damp and 
in too large masses, ferments and turns dark. In decomposing, 
sufficient heat is developed to be insupportable when the hand is 
thrust into the mass, and vapors begin to be emitted. When the 
water is almost entirely evaporated, the decomposition continues, 
and the hay becomes carbonized little by little ; and then the 
charred portion, like peat — peat-cinders mixed with charcoal, sul- 
phurous pyrites and lignite, etc. — becomes a kind of pyrophorus, 
by virtue of its great porosity and of the large quantity of mat- 
ter exposed to high oxidation. Under the influence of air in 
large amount, this charcoal becomes concentrated on the surface 
to such a degree that the mass reaches a temperature which re- 
sults in its bursting into flames. The preventives for this danger 
are care that the hay in the lofts is kept perfectly dry, that it is 
well stacked, and that it is stored in small heaps rather than in 
large masses. 

Hay, To estimate the weight of. — Allow 1 cwt. of hay to the 
cubic yard. 

Horse, Power of. — The greatest amount an average horse can 
pull in a horizontal line will raise a weight of 900 lbs. ; but he 
can only do this momentarily; in continued exertion, probably 
half this amount is the limit. 

Horses, Bedding for, — Sawdust serves this purpose well. 

Horses, Buying, Hints for. — Examine the eyes in the stable, 
then in the light ; if they are in any degree defective, reject. Exa- 
mine the teeth to determine the age. Examine the poll or crown of 
the head, and the withers, or top of the shoulders, as the former 
is the seat of poll evil, and the latter that of fistula. Examine 
the front feet ; and if the frog has fallen, or settled down be- 
tween the heels of the shoes, and the heels are contracted, reject 
him, as he, if not already lame, is liable to become so at any 
moment. Next observe the knees and ankles of the horse you 
desire to purchase, and, if cocked, you may be sure that it is the 
result of the displacement of the internal organs of the foot, a 
consequence of neglect of the form of the foot, and injudicious 
shoeing. Examine for interfering, from the ankle to the knees, 
and if it proves that he cuts the knee, or the leg between the knee 
and the ankle, or the latter badly, reject. '' Speedy cuts" of the 
knee and leg are most serious in their effects. Many trotting 
horses, which would be of great value were it not for this single 
defect, are by it rendered valueless. Carefully examine the hoofs 
for cracks, as jockeys have acquired great skill in concealing 
cracks in the hoofs. If cracks are observable in any degree, re- 
ject. Also both look and feel for ringbones, which are callosities 
on the bones of the pastern near the foot ; if apparent, reject. 
Examine the hind feet for the same defects of the foot and 
ankle that we have named in connection with the front feet. 
Then proceed to the hock, which is the seat of curb, and both 



210 THE FARM. 

bone and blood spavins. The former is a bony enlargement of 
the posterior and lower portion of the hock-joint ; the second a 
bony excrescence on the lower, inner, and rather anterior portion 
of the hock ; and the last is a soft enlargement of the synovial 
membrane on the inner and upper portion of the hock. They are 
either of them sufficient reason for rejecting. See that the horse 
stands with the front feet well under him, and observe both the 
heels of the feet and shoes to see if he " forges " or overreaches ; 
and in case he does, and the toes of the front feet are low, the 
heels high, and the heels of the front shoes a good thickness, 
and the toes of the hind feet are of no proper length, reject him ; 
for if he still overreaches with his feet in the condition described, 
he is incurable. If he props out both front feet, or points them 
alternately, reject. In testing the driving qualities, take the reins 
while on the ground, invite the owner to get in the vehicle first, 
then drive yourself. Avoid the display or the use of the whip ; 
and if he has not sufficient spirit to exhibit his best speed without 
it, reject. Should he drive satisfactorily without, it will then 
be proper to test his amiability and the extent of his training in 
the use of the whip. Thoroughly test his walking qualities first, 
as that gait is more important in the horse of all work than great 
trotting speed. The value of a horse, safe for all purposes with- 
out blinds, is greatly enhanced thereby. Purchase of the breeder 
of the horse if practicable ; the reasons are obvious. 

PIORSES, Common-sense treatment for. — (1) All horses must 
not be fed in the same proportions, without due regard to their 
ages, constitutions, and work. (2) Never use bad hay because it is 
cheap ; there is no nourishment in it. (3) Damaged corn brings 
on inflammation of the bowels and skin diseases. (4) Chaff is 
better for old horses than hay, because they can chew and digest 
it better. (5) Mix chaff with corn or beans. (6) There is not 
sufficient nutritive body in either hay or grass alone to support a 
horse under hard work ; in such case the food should chiefly be 
oats. (7) For a saddle or a coach horse, half a peck of sound 
oats and 18 lbs. of good hay is sufficient ; if the hay is not good, 
add a quarter of a peck more oats. (8) Rack feeding is wasteful ; 
feed with chopped hay from a manger. (9) Sprinkle the hay 
with water that has salt dissolved in it, because it is pleasing to 
the animal's taste and more easily digested. A teaspoonful of 
salt in a bucket of water is sufficient. (10) Oats should be 
bruised for an old horse, but not for a young one. (11) Cut grass 
should always be given in spring to horses that can not be turned 
out into the fields ; it is very cool and refreshing. (12) Water 
horses from a pond or stream, rather than from a spring or well, 
because the water from the latter is generally hard and cold, while 
the former is soft and comparatively warm. The horse prefers 
soft muddy water to hard water, though never so clear. (13) A 
horse should have at least a pailful of water morning and even- 
ing, or (still better) four half pailfuls at four several times in 
the day, because this assuages his thirst without bloating him. 
He should not be made to work directly after a full draft of 
water. (14) Do not allow a horse to have warm water to drink, 
since, if he has to drink cold water after becoming accustomed to 



THE FARM. 211 

warm, it will give hiin colic. (15) Do not work a liorse when 
. he refuses food after drinking ; he is thoroughly fagged out. 

Horses, Dead, To utilize. — Drag the body to some out-of-the- 
way part of the farm and sprinkle quicklime over it. Then cover 
witli about twenty-five wagon-loads of muck or sods. In a year 
an excellent manure-heap will be at your disposal. Smaller ani- 
mals may be similarly utilized. 

Horses, Scratches on — These may be cured by washing the 
legs in warm, strong soap-suds, and then in beef brine. 

Horses, To keep flies from. — Make an infusion of 3 hand- 
fuls of walnut leaves in 3 qts. of cold water. Let this stand 
over night and boil for a quarter of an hour in the morning. 
When cold, rub it over the ears, neck, and other irritable parts 
of the animal, with a moist sponge. 

Horses, Wounds on. — If .suppuration is inevitable, use car- 
bolic acid combined with glycerine or linseed-oil in the propor- 
tion of 1 to 20. It may be applied night and morning with a 
feather. The wound must be kept clean, and, in the case of 
backs and shoulders, all pressure removed by small pads of 
curled horse-hair, sewed on the harness above and below the sore. 

Ice, Compressed. — Thin ice from ponds, or small pieces left 
after cutting blocks from larger bodies of water, may be stored 
in a profitable manner, and at the same time its preservation in- 
sured, by compressing it into solid blocks by means of any simple 
press. In localities where ice is not attainable, snow might 
easily be treated in the same way. 

Ice, To keep. — Select a shady spot, on the north side, if possible, 
of a clump of trees. Throw up a circular mound, some 12 in. in 
heiglit and at least 15 ft. in diameter, flattening the summit care- 
fully, and leaving a trench around the eminence, 2 ft. in width 
and 18 in. in depth. In gathering the ice, there is no necessity of 
cutting into uniform shape or of seeking large pieces. Fill up 
the carts with any kind of fragments, transport them to the 
mound, and dump them on a platform made of a few planks. 
Ram the surface of the mound hard and firm, cover with sawdust, 
and then place the first layer of ice, which should previously be 
cracked into small pieces, for which purpose the men should be 
provided with wooden mallets. As each layer is put on the stack, 
the ice should be thoroughly pounded, both above and at the sides, 
so as to form a huge block of ice, the shape of which will be 
sliffhtly conical. 

When the stack is completed, it will require two coverings of 
straw, one lying upon the ice and the other supported on a wooden 
framework about 18 in. outside the first covering. 

The layer of straw next the ice must be well beaten and flat- 
tened down upon it, and when this is done, be 12 in. in thickness. 
The framework, upon which a similar thickness of straw is placed, 
may be formed by inserting stout larch or other poles of a suitable 
length round the base in a slanting direction, so that they can be 
readily brought together at the top, and securely fastened with 
stout cord. From six to eight of these will, when joined together 
"by means of strips of wood fixed about 12 in. apart, afford ample 



212 THE FARM. 



support for the second covering of the straw. This must be pat 
on nicely, so as to prevent the possibility of the rain's penetrating 
to the inner covering. By this arrangement there will be a body 
of air, which is one of the most effectual non-conductors known, 
between the two coverings of straw. To effect a change of the 
inclosed air, when rendered needful by its becoming charged with 
the moisture arising from the melted ice, a piece of iron or earth- 
enware pipincr a few inches in diameter should be fixed near the 
apex, one end being just above the straw, and the other end 
reaching into the inclosed space. The pipe can be readily opened 
or stopped up, as may appear necessary, but as a rule it will suf- 
fice to open the pipe once a week, and allow it to remain open 
for about two hours. This should be done early in the morning, 
as the air is then much cooler than during the day or in the even- 
ing. 

In removing ice from the stack, the early morning should be 
taken advantage of, because of the waste which must naturally 
ensue from a rush of warm air at midday. That removed can be 
placed in a cellar, or even an outhouse, and be enveloped in saw- 
dust until required. The ice must be taken from the top ; and 
when the first supply is obtained, a good quantity of dry sawdust 
should be placed over the crown. 

Insect-Catching Device, A simple. — Cover the inside of an 
old tub with liquid tar, and at twilight put a liprhted lantern with- 
in, leaving the whole out over night. The bugs, attracted by 
the light, try to reach the lantern, and are caught and held fast by 
the tar. 

Insects on Plants, To discover. — If the leaves of the plant 
seem reddish or yellow, or if they curl up, a close inspection will 
generally disclose that the plants are infested by a very small 
green insect, or else with red spider, either of which must be de- 
stroyed. For this purpose, scald some common tobacco with wa- 
ter until the latter is colored yellow, and when cold, sprinkle the 
leaves of the plants with it. It is a good plan to pass the stems 
and leaves of the plants between the fingers, and to then shake 
the plant and well water the bed immediately afterward ; the lat- 
ter operation destroys a large proportion of the insects shaken 
from the plant. 

Insects, To protect cattle from. — Rub a very weak solution of 
carbolic acid through the hair. 

Manure, Salt as. — Salt should never be applied other than in a 
pulverous state, and never employed on impervious, cold, and hu- 
mid soils. The best manner to use it is to combine it with 
other manures, a dose of 2 cwt. to the acre being suflBcient. 
When selected to destroy insects, it should be applied before 
sunrise. In the case of cereals, salt strengthens the stems, and 
causes the ears to fill better, and favors the dissolution and 
assimilation of the phosphates and silicates. It acts vigorously 
on potatoes, and can be detected in their ashes to the extent of 
one half or one per cent. Asparagus is a veritable glutton in the 
presence of salt. A dose of 3 cwt. per acre acts without fail on 
beet, injuring its value for sugar purposes, but enhancing it for 
the feeding of cattle. Colza has as marked a predilection for salt 



THE FARM. 213 

as asparagus ; and in Holland, where the culture of peas is so ex- 
tensive, salt is something like a necessity. Mixed with hay in 
the proportion of 4 ozs. to 1 cwt., the fodder is more appetizing ; 
but the best way to feed it to animals is to allow them to enjoy it 
in the form of rock salt. 

Manure, Soot. — Save the soot that falls from the chimneys, 
when the latter are cleaned. Twelve quarts of soot to a hogshead 
of water makes a good liquid manure, to be applied to the roots 
of plants. 

Manure. — The bodies of king crabs, often found along the sea- 
shore, when decayed and mixed with sawdust, straw, muck, or 
similar material, make an excellent manure. Land so poor that 
no wheat could be grown on it, has been so enriched by the appli- 
cation of this compost, that from 25 to 30 bushels to the acre 
have been raised. 

Moss ON Trees, To destroy. — Use a whitewash of quicklime and 
wood-asLes. 

Mowing Machines, Draft of. — The power required to drive a 
mowing machine at work may be resolved into direct draft and 
side draft. A good mowing machine should be so balanced be- 
tween the driving wheels and the cutter bar, by placing the line 
of draft nearer or further from the heel of the bar, that ordinarily 
there will be little or no side draft. If so placed, the end of the 
tongue will sometimes, when at work, be drawn toward the stand- 
ing grass, and sometimes thrown away from it by the side draft. 
Practically, side draft is of small account in a good machine. The 
direct draft depends upon three causes, and may be resolved into 
three parts : 1, The draft of the machine itself, on its own wheels, 
on the ground ; 2, The power required to give motion to the gear- 
ing and the knife ; 3, The resistance offered by the grass or other 
substance cut. The power required to draw the machine on its own 
wheels depends upon the size of the wheels, the perfection of the 
axles, and the smoothness of the ground, and, other things being 
equal, upon the weight of the machine ; and in a machine weigh- 
ing 600 lbs., should not, on a smooth firm turf and level field, be 
more than 75 to 100 lbs Adding to the weight of the machine 
would add to the draft just in proportion, whether that added 
weight be in the machine or in a driver on it. Suppose the ma- 
chine to weigh 600 lbs. and the draft to be 80 lbs., put a driver of 150 
lbs. on the seat, and you have increased the draft 25 per cent, or 
to 100 lbs. , while the power required to drive the knife and to 
cut the grass remains unchanged, and you have only increased 
the draft 20 lbs. The power to drive the knife and gearing de- 
pends upon the perfection of the gearing and the weight and 
velocity of the knife. A machine that in proper order may not 
require more than 10 or 20 lbs. of power, may require ten or 
twenty times that amount from deficiency of oil, collection of dirt 
in the gearing, gum on the knife, or loosening of the connections 
of the pitman by wearing or otherwise. The resistance of the 
grass to be cut will vary with every change of condition, kind, and 
thickness of grass, and every variation in the condition of the 
knife and rapidity of stroke. The greater the velocity of a cut- 
ting edge, after the velocity is once obtained, the less power is 



214 THE FARM. 

required to do a given amount of work. The direct draft of a 
good machine, working under the most favorable circumstances, 
has been determined by experiment to be less than 300 lbs. ; but 
those favorable conditions are not always to be obtained, so that 
the draft must many times be much heavier. The power of a 
machine to cut, otlier things being equal, depends upon the hold 
the wheels have upon the ground ; when the second and third 
causes combined are sufficient to overcome the hold the wheels 
have, the latter slide, the knife stops, the machine is clogged. 
Tlie heavier the machine, the less likely this is to occur ; putting 
a heavy driver on the seat will sometimes carry a machine through 
when with a lighter one it would clog. When the knife reaches 
the end of the stroke, its momentum is considerable, and it re- 
quires nearly as much power to stop it as it did to start it to make 
the stroke ; it would require quite as much if it were not for the 
loss of some power by the friction of the knife in the guards. Now 
if the joints of the pitman and connections are all perfect, this 
stopping occurs when the crank passes the centre of the shaft 
driving it, and the remainder of the momentum of the knife is 
expended upon the crank in the direction of its length and at 
right angles to the driving power, so that none of that is used up 
in stopping the knife. But if these joints of the pitman are loose, 
so that there is a little play, and the crank can pass the centre be- 
fore the knife reaches the end of the stroke, this momentum will 
be expended in opposition to the driving power, and will of course 
increase the power necessary to work the machine by so much as 
is necessary to overcome the momentum of the knife ; again, the 
crank beginning to act upon the knife after it has passed the cen- 
tre to make the return stroke, the knife must start with a greater 
velocity, causing another loss. Now, put the same machine into 
the grass, and the grass operates to stop the knife as soon as the 
crank allows it to stop, thus saving the momentum that was ex- 
pended upon the crank in opposition to the driving power, and 
also shortening the stroke and saving power that way. Suppos- 
ing, to illustrate, that there is a play of -J inch in the joints, then 
the knife running out of the grass will be thrown to the extreme 
lengtli each way, and will add 1 inch to the length of the stroke, 
increasing the power necessary to make it. If it requires a cer- 
tain number of pounds power to make a stroke of 3 inches in 
length, it will require 33J- per cent more power to make a stroke 
of 4 inches in length in the same time. Whenever these amounts 
of power lost in this way equal the power required to cut the 
grass, then the machine will draw just as heavily out of the grass 
as in it. From these premises many deductions may be made as 
to the care and practical use of mowing machines. 

Nest Eggs, To make. — Take an ordinary hen's egcr^ break a 
small hole in the small end, about f of an inch in diameter, ex- 
tract the contents, and, after it is thoroughly clear inside, Ull it 
with powdered slaked lime, tamping it in order to make it con- 
tain as much as possible. After it is full, seal it up with plaster 
of Paris, and you have a nest egg which can not be distinguished 
by the hen from the other eggs, and one which will not crack 
(like other eggs) by being frozen. 



THE FARM. 215 

Onions, To transplant. — Plant them tightly in the soil, with 
the leaves pointing to the north. When thus placed, after the 
vegetables take root, the sun will draw the stalks vertical. 

Oxen, Food consumed by. — An ox will consume 2 per cent of 
his weight of hay per day to maintain his condition. If put to 
moderate labor, an increase of this quantity to 3 per cent will en- 
able him to perform his work and still maintain his flesh. If he 
is to be fatted, he requires about 4^ per cent of his weight daily 
in nutritious food. 

Painting Boats. — Boats should be painted vrith raw oil. 
Boiled oil used in the paint is very apt to blister and peel from 
the wood. 

Paris Green, To use. — In using Paris green to exterminate 
the potato bugs, the poison should be mixed with the cheapest 
grade of flour, 1 lb. green to 10 lbs. flour. A good way of 
applying it to the plants is to take an oLl 2 quart tin fruit-can, 
melt off the top, and put in a wooden head in which insert a 
broom-handle. Bore a hole in the head, also, to pour the powder 
in, and then punch the bottom full of boles about the size of No. 
6 shot. Walk alongside the rows, when the vines are wet with 
dew or rain, and make one shoot at each hill. 

Pastures, Seeding. — Select varieties of seeds that spring up 
in succession, so that a good fresh bite may be had from spring to 
fall. 

Pear Culture. — Pears have a tendency to crack when the 
trees stand in soil which is deficient iu lime and potash. Com- 
mon wood-ashes contain these salts nearly in the proportions that 
pear-trees on such soil require — 40 per cent of potash and 80 per 
cent of lime. By applying wood-ashes at the rate of four hun- 
dred bushels to the acre, after the fruit had formed and cracked, 
the disease was totally eradicated by the next season. 

Peat, Estimating quantity of. — Peat, as ordinarily in the bed, 
will weigh from 2100 to 2400 lbs. per cubic yard ; and if drained 
in the bed, 1340 to 1490 lbs.; and air-dried, 320 to 380 lbs., when it 
will be found to be reduced to about i or ^ its original bulk. 

Peat, Facts concerning. — When saturated with salt water, peat 
is generally unfit for heating purposes. The fine, clay-like pow- 
der found underlying peat-beds, of a yellowish white color, is 
composed of shields of infusorial animalculae, and forms a supe- 
rior powder for polishing metals. In working a bed of peat, the 
first step will be to ascertain if drainage is necessary ; and, se- 
condly, how it can be effected and at the least cost. If the bed 
can not be economically drained, resort must be had to mechani- 
cal excavation. It is best not to drain a bed below the level to 
which you can effectually work out in a season, unless you can 
close the outlet drain to allow it to fill again with water for the 
winter, for the reason that drained peat that has been frozen is 
apt to disintegrate after thawing, and become impoverished for a 
solid homogeneous fuel. Peat that has been well manipulated 
and dried for fuel rarely holds more than 10 per cent of moisture, 
and it will not afterwards become saturated with water, even by 
immersion for an entire winter. A cubic yard of closely-packed 



216 THE FARM. 

peat fuel will weigh from 1620 to 2180 lbs., and the heating value 
ofl lb. of such peat is equal to even 1| lbs. wood ; one cord of 
good wood will weigh almost 4200 lbs., and 1 cord of peat fuel 
will weigh about 3750 lbs., showing a gain in space as well as in 
greater heating power. 

Plants, Creeping, Pegging down. — To propagate lobelias and 
verbenas, the first bloom should be picked off, and the branches, 
as they extend, should be pegged down closely to the surface of 
the mould. The branches will then take root as they lengthen, 
and by thus drawing a large amount of sustenance from the soil, 
they will bloom very freely and cover a large space. A verbena 
may thus be made to cover a square yard, and a lobelia a square 
foot of ground. 

Plants, Iron and ashes for. — White flowers, or roses, that have 
petals nearly white, will be greatly improved in brilliancy by 
providing iron sand and unleached ashes for the roots of growing 
plants. Ferruginous material may be applied to the soil where 
flowers are growing, or where they are to grow, by procuring a 
supply of oxide of iron, in the form of the dark -colored scales 
that fall from the heated bars of iron when the metal is hammer- 
ed by the blacksmiths. Iron turnings and iron filings, which 
may be obtained for a trifle at most machine-shops, should be 
worked into the soil near flowers, and in a few years it will be 
perceived that all the ihinute fragments will have been dissolv- 
ed, thus furnishing the choicest material for painting the gayest 
colors of the flower-garden. If wood-ashes can be obtained readi- 
ly, let a dressing be spread over the surface of the ground, about 
half an inch deep, and be raked in. 

A dressing of quicklime will be found excellent for flowers of 
every description. It is also of eminent importance to improve 
the fertility of the soil where flowers are growing, in order to 
have mature, plump, ripe seed. Let the foregoing materials be 
spread around the flowers, and raked in at any convenient period 
of the year. 

Plants, Potting. — The mould for potting should be light and 
loamy, the fertilizing material used being well decayed. If the 
soil is rich of itself, it is better to be either very sparing with the 
fertilizer or to dispense with it altogether. In the bottom of the 
pot place several small broken pieces of crockery or similar ma- 
terial to assist the drainage ; and in setting the plant, be careful 
to keep it well down in the pot, and to press the mould moderately 
around the roots. The surface of the mould should be about half 
an inch below the level of the top of the flower-pot. Slips should 
be planted close to the sides of the pot, and in small pots. When 
a plant becomes pot-bound, that is, when the roots have become 
matted around the sides and bottom of the pot, the plant, so soon 
as it has ceased blooming, should be re-potted in a larger pot. It 
is not necessary to remove any of the mould from tlie roots, but 
simply to fill in the space in the larger pot with new and rich 
mould. 

Plant-Protector, A newspaper. — A convenient number of 
newspapers may be pasted together, and the edges folded over 
strings, thus making a screen which, suspended over the newspa- 



THE FARM. 217 

pers spread loosely over tlie plants, would give tlie young shoots 
an excellent protection in the severest cold weather, and from 
the sun's rays in summer. 

Plants, Selecting. — Choose those whose leaves are of a deep 
green, and in all cases those which are short and bushy, and 
have no bloom upon them. If, however, they are in bloom, cut 
off the flowers before planting, which will only delay the bloom- 
ing a few days, and will greatly strengthen the plant. If the 
plants have been reared in a greenhouse or under frames, keep 
them a few days before setting them in beds, placing them out of 
doors in the daytime, and taking them in at night, in order to 
make them hardy and prevent them suffering from the cool night 
air. If the plants are placed in a cold-frame, either before or 
after being planted in the beds, be careful to lift the frame during 
a great part of the daytime, otherwise the moisture which gathers 
on the inside of the glass will fall upon the plants and infallibly 
kill them by what is called dampness. 

Plants, Treating unhealthy. — Mr. Peter Henderson, the cele- 
brated horticulturist, says : Whenever plants begin to drop their 
leaves, it is certain that their health has been injured either by 
over-potting, over-watering, over-heating, by too much cold, or 
by applying such stimulants as guano, or by some other means 
having destroyed the fine rootlets by which the plant feeds, and 
induced disease that may lead to death. If the roots of the plant 
have been injured from any of the above-named causes, let the 
soil in which it is potted become nearly dry ; then remove the 
plant from the pot, take the ball of soil in which the roots have 
been enveloped, and crush it between the hands just enough to 
allow all the sour outer crust of the ball of earth to be shaken off ; 
then re-pot in rather dry soil (composed of any fresh soil mixed 
with equal bulk of leaf-mould or street-sweepings), using a new 
flower-pot, or having thoroughly washed the old one, so that the 
moisture can freely evaporate through the pores. Be careful not 
to over-feed the sick plant. Let the pot be only laro^e enough to 
admit of not more than an inch of soil between the pot and ball of 
roots. After re-potting, give it water enough to settle the soil, 
and do not apply any more until the plant has begun to grow, 
unless, indeed, the atmosphere is so dry that the moisture has 
entirely evaporated from the soil ; then, of course, water must 
be given, or the patient may die from the opposite cause — starva- 
tion. The danger to be avoided is in all probability that which 
brought on the sickness, namely, saturation of the soil by too 
much water. 

Potatoes, Hoeing. — By drawing up the earth over the pota- 
to in sloping ridges, the plant is deprived of its due supply of 
moisture by rains, for when they fall the water is cast into the 
ditches. Further, in regard to the idea that, by thus earthing 
up, the number of tubers is increased, the effect is quite the re- 
verse ; for experience proves that a potato, placed an inch only 
under the surface of the earth, will produce more tubers than one 
planted at the depth of a foot. 

Potato Sprouts, Poisonous. — The sprouts of the potato con- 
tain an alkaloid, termed by chemists solanine, which is very poi- 



218 THE FARM. 

sonous if taken into the system. It does not exist in the tubers 
unless they are exposed to light and air, which sometimes occurs 
from the accidental removal of the earth in cultivation. 

Potatoes, Storinc?. — A plan, tested successfully for eight 
years, is to sprinkle the floor with fine unslaked lime, over which 
a layer of potatoes 4 or 5 inches in depth is spread. Then sprin- 
kle again with lime, and add another layer of potatoes the same 
depth as before, and thus continue till the whole are disposed of. 
The lime used is about one fortieth part by measure of the pota- 
toes. 

Potatoes thus treated have never become infected with disease, 
and when disease was already existing it has not spread ; besides 
which, the quality of the potatoes has been rather improved than 
otherwise by the treatment, especially where they were watery 
or waxy. 

Poultry-Houses, Purifying. — Lime is an excellent purifier, 
and, when carbolic acid is added to the whitewash, will effectually 
keep away vermin from the walls. After every cleaning of the 
floor it should be sprinkled with carbolic acid ; dilution, twenty 
of water to one of acid. This is one of the best disinfectants and 
antiseptics known, and is not used as much as it deserves. The 
roosts should be sprinkled with it every week. This whitewash- 
ing should be done twice at least, better three times a year. The 
nests of sitting hens should be sprinkled with carbolic acid to 
keep off vermin ; and the coops also, where young broods are kept 
for a time, should be purified in this way. If a hen gets lousy, 
the dilute acid will destroy the lice, if put under the wings, and 
on the head and neck. Wood-ashes are excellent to be kept in 
fowl-houses for hens to dust themselves with. They are much 
more effectual than sand, but sand should also be kept for a bath. 

Propagating Plants. — To propagate geraniums and calceo- 
larias, do not let the plants flower too soon, but pinch off the 
first appearing bloom, and pinch out the eyes of all straggling 
branches, which will immediately throw out side-shoots, thus 
forming very healthy and strong as well as good- shaped plants. 
Give preference to those plants which have their branches close 
to the surface of the soil. 

Pruning Trees. — The proper cut is called the " clean cut," and 
is made by cutting at an angle of 45°, beginning at the back of the 
bud, and finishing slightly above it. When pruned in this way the 
wound readily and rapidly heals, and commences to be covered with 
new wood as soon as the young bud pushes into growth. Pruning 
should always be done with a keen-edged knife, holding the 
shoot in the left hand, and making one sharp, quick draw. The 
operation should be delayed until the middle of February, and 
performed between that time and the middle of March. 

Rats, Extermination of, by bisulphide of carbon — Insert a 
lead pipe into the holes, and pour in bisulphide of carbon. This* 
should only be used out of doors, never in buildings. An ounce 
and a half of the liquid is suflScient to pour in at a time. 
Where there are several holes near together, stop all but the one 
in which the bisulphide is poured, with bricks. 



THE FARM. 



219 



Red Spiders, To exterminate. — Syringe tlie plants freely with 
water once or twice a day, taking care to wet the under side of 
the leaves. Keep the air of the room moist, by setting pans of 
water on the flues, heating-pipes, or register ; give all the light 
possible, and ventilate freely whenever the weather will permit. 
When the soil is dry, give sufficient water to moisten all the soil 
in the pot, and water no more until the surface is dry again. If 
plants seem stunted or sickly, repot them in fresh, rich soil, or 
use some other means to induce a healthy growth. The red spi- 
der is any thing but an aquatic insect, and will yield to the hy- 
dropathic treatment if it is persisted in. 

Sand is the best substance in which to preserve carrots through 
the winter. It should be perfectly dry. It will keep the roots 
crisp and prevent softening. 

Spawn-Carrying Device. — The apparatus represented here- 




FISH-SPAWN CARRYING APPARATUS. 

with IS a new invention of Mr. Seth Green. It consists of a sim- 
ple wooden box, of a convenient size to be carried in the hand by 
means of the handle above. Its joints are covered with tin. Inside 
are numerous small trays made of wood, covered below with can- 
ton flannel. The upper tray, shown in the foreground, is pro- 
vided with a hinged cover of the same materials. The spawn is 



220 THE FARM. 

placed upon tlie bottom of the trays, together with moss or sea- 
weed, and kept moist. The temperature of the room may be so 
regulated that the spawn can be hatched in from 50 to 150 dayt*. 
Brook-trout, salmon trout, white-fish, and salmon-eggs have beer 
transported with success, over long joarneys, by this means. 

Seeds, Germination of. — The germination of seeds can be 
watched at every stage of its progress by laying the seeds between 
moist towels and placing the latter between plates. The towels 
can be lifted without damage to the tender sprouts. 

Seeds, Vitality of. — Seed will not germinate if they are too 
old, and disappointment and delay often result. Experience of 
seedsmen indicates that, if properly gathered and preserved, 
beans will retain vitality 2 years , beet, 7 ; cabbage, 4 ; carrot, 2 ; 
sweet corn, 2 ; cucumber, 10 ; lettuce, 3 ; melon, 10 ; onion, 1 ; 
parsnip, 1 ; peas, 2 ; radish, 3 ; squash, 10 ; tomato, 7 ; turnip, 4. 

Sheep, To protect from dogs. — An old sheep-raiser says that 
the most efficacious plan is to provide 15 or 20 sheep, in a flock 
of 100, each with a globular bell about the size of a teacup. 

Sleigh. — The length of the double whiffletree and the neck- 
yoke for a sleigh should be just as long as the sleigh is wide 
from the centre of one runner to the other. 

Slugs, Rose, To destroy. — Wood-ashes must be sifted on early 
in the morning while the leaves are damp, the branches being 
turned over carefully, so that the under sides of the leaves, to 
which the young slugs cling, may get their share of the sif tings. 
If the night has been dewless, in order to make the work tho- 
rough, first sprinkle the bushes, and the ashes will then cling to 
the slugs, to their utter destruction. 

Stumps, Clearing off. — In the autumn, bore a hole 1 to 2 inch- 
es in diameter, according to the girth of the stump, vertically in 
the centre of the latter, and about 18 inches deep. Put into it 
from 1 to 2 ozs. saltpetre ; fill the hole with water, and plug up 
close. In the ensuing spring, take out the plug, pour in about ^ 
gill kerosene oil and ignite it. The stump will smoulder away, 
without blazing, to the very extremity of the roots, leaving no- 
thing but ashes. 

Stables, To remove rank smell of. — Sawdust, wetted with sul- 
phuric acid, diluted with 40 parts of water, and distributed about 
horse-stables, will remove the disagreeable ammoniacal smell. 

Sub-Soil Drain, A simple. — An excellent subsoil drain may 
be made by digging a trench, and filling in the bottom with 
sticks of wood, compressing them together with the feet, and 
then covering them with the mould. The effectiveness of such 
a drain will endure for several years, and the final decay of the 
wood will serve to enrich the soil. 

Sumac, Cultivation and preparation of. — Sumac is largely used 
in tanning the finer kinds of leather, especially in the manufac- 
ture of the hard-grained moroccos and similar goods. It is also 
employed as the base of many colors in calico and delaine print- 
ing. The only trouble is in curing it properly. This must be 
done with all the care that is bestowed upon tobacco or hops. 
Exposure, after cutting, to a heavy dew injures it, and a rain- 



THE FARM. .221 

Storm detracts materially from its value. It is cut wlien in full 
leaf ; and when properly dried is ground, leaves and sticks toge- 
ther. An acre in full bearing will produce not less than three 
tons ; and when fit for market, it is worth from eighty to one 
hundred dollars a ton. The manufacturers, as the eurers are 
called, pay one cent a pound for it in a green state. The Com- 
missioner of Agriculture advises to plant in rows, in order to cul- 
tivate between, either by seed or cutting of the roots. We should 
advise cuttings by all means, as sumac is as tenacious of life as the 
blackberry or horse-radish. It will never need but one planting, 
and the crop can be gathered any time from July to the time of 
frost. If it is cut later in the season, and annually, the leaves 
and the stocks can be ground together. If the cutting is delayed 
until the stock has formed into solid wood, the leaves must be 
stripped from the stock, and the stock is thus wasted. It is 
doubtful if any thing is gained in the weight of leaves after the 
middle of July, at which time almost every tree has completed 
what is called first growth, for the season. 

Sumac, Mordants for dyeing with. — The mordants used for 
dyeing" with sumac are either tin, acetate of iron, or sulphate of 
zinc. The first gives yellow, the second gray or black, according 
to strength, and the third greenish-yellow. 

Tools, Paint for. — White lead ground in oil, miugled with 
Prussian blue, similarly prepared, to give the proper shade, and 
finally mixed with a little carriage -varnish, is an excellent and 
durable paint for farm-machinery and agricultural tools. 

Trees, Felling. — To find the height at which a tree must be 
cut, so that its top will strike a given point on the ground : 
Square the height of tree, and the given distance from tree to 
point. Divide the difference of these squares by twice the height 
of tree, and the quotient will be the height from the ground 
where the tree has to be cut. Example : Height of tree =60 feet, 
distance of point to the tree 20 feet ; then 60^=3600, 20'=400, 
difeerence=3200. 3200h-(2x60)-26.6 feet. 

Trees, Fruit, To protect against mice. — Apply to the bark a 
mixture of tallow, 3 parts, tar, 1 part, hot. 

Trees, Girdled, To save. — If possible, bank up earth about 
the truck to above the level of the girdle. If the wounded parts 
are too high, bind on clay with a bandage. The sooner the sur- 
face is protected after injury the better. The death of the tree 
is caused by the seasoning of the sap-wood. 

Trees, Young, in hot weather. — If the trunk is fully exposed 
to the sun, it should be protected from intense heat. A couple 
of boards, tacked together like a trough and set up against the 
trunk, will furnish the required shade ; or the trunk may be 
bound with a hay-rope, or be loosely strawed up as for winter 
protection. 

Trichina in Pork, A cause of. — It has lately been found that 
swine may become infested with trichinae through eating carrion, 
or even decayed vegetable substances. This is a point worth 
consideration by farmers who incline to the belief that dead 



222 THE FARM. 

chickens, putrid swill, or any other filth about the place, is legi- 
mate food for the pig. 

Turnips, To protect from fly. — Use lime, slaked just before 
application. Sow it by hand over the plants ; or sow brimstone 
with the seed. A simple way of removing the insects from the 
plants is to mount a board two feet square on wheels, cover the 
under side of the board with tar, and straddle it over the rows, 
drawing it from end to end of the latter. The insects will jump 
off on the pitch and be caught. 

Waterfall, To determine the height of, in a running stream. 
— A small temporary dam, unless one exists, must be made, so 
as to secure a still surface. Take two poles, sufficiently long to 
reach from the bottom of the water to the required line-level. 
Make a plain mark or notch on both sticks, at a distance from 
the upper end equal to the distance of the intended line- level 
above the water, marking that distance in feet and inches. Push 
the poles down through the water into the earth at the bottom until 
the notches are both at the level surface of the water, care being 
taken to have the poles plumb and at a convenient distance apart. 
Sight across the tops of these two, and set as many more as may 
be desired to run the line of level to the desired point, and the 
tops being ranged accurately by the first two, will show a water- 
level so many feet above that of the water. It is estimated that 
this is a more accurate way than the use of the ordinary spirit- 
level. 

Water for Fish-Ponds — Lead- pipe will not do to conduct 
water to fish-ponds. It is likely to poison the fish. 

Weeds, Destroying. — Some weeds can be killed and prevented 
from growing in garden- paths, by watering the ground with a 
weak solution of carbolic acid, 1 part pure crystallized acid to 
2000 parts water. Sprinkle from a watering-pot. 

Worms, Currant and Gooseberry, Remedy for. — The best 
is powdered white hellebore, obtainable at any druggist's. Put 
the powder in a common tin cup, tying a piece of very fine muslin 
over the mouth. Fasten the apparatus to the end of a short 
stick, and dust the powder through the muslin lightly upon the 
bushes. Do not work on a windy day, and stand to windward 
during the operation, as, if taken into the nostrils, the hellebore 
excites violent sneezing. The same material is a good remedy 
for cucumber-beetles. 



HOUSEHOLD HINTS. 



Ants, Red, To drive away. — Sprigs of wintergreen or ground 
ivy will drive away red ants ; branches of wormwood will serve 
the same purpose for black ants. The insects may be kept out 
of sugar-barrels by drawing a wide chalk mark around the top, 
near the edge. 

Aquarium, To make and stock an. — One of the first principles, 
in constructing a tank for an aquarium, is to give the water the 
greatest possible exposure to the air. The simple rectangular 
form is the best. This is generally constructed of iron and olass ; 
the iron should be japanned, and the glass be French plate, to 
insure brilliancy and strength. The breadth and height of the 
tank should be about one half of the length. Cheap tanks can be 
made of wood and glass, the frame and bottom being of wood, 
and the sides of glass. In order to make the joints watertight, 
care must be taken to get a proper aquarium putty or cement. 
The following is a good recipe : Put an eggcupf ul oil and 4 ozs. 
tar to 1 lb. resin ; melt over a gentle fire. Test it to see if it has 
the proper consistency when cooled ; if it has not, heat longer or 
add more resin and tar. Pour the cement into the angles in a 
heated state, but not boiling hot, as it would crack the glass. 
The cement will be firm in a few minutes. Then tip the aqua- 
rium in a different position, and treat a second angle likewise, 
and so on. The cement does not poison the water. It is not ad- 
visable to make the aquarium of great depth ; about eight inches 
of water is sufficient. In regard to the light, great care must be 
taken. Too much often causes blindness, and is a common 
source of disease. The light fish receive in rivers comes from 
above, and an aquarium should be constructed so as to form no 
exception to tbis rule. All cross-lights should be carefully 
avoided, at least if the light is very strong. Never place the 
aquarium in front of a window so that the light passes through it ; 
for, when viewing an aquarium, the source of light should 
come from behind us. Not enough light is as injurious as too 
much, and causes decay of the vegetation. Having constructed 
a watertight aquarium, the bottom is strewn over with clean 
sand to the depth of 1 to 3 inches ; on this a little gravel is 
spread ; the a a few stones or rock- work. Heavy large rocks 
should be avoided ; they displace a large amount of water, and in- 
crease the danger of breaking the glass sides. Pumice-stone, well 
washed, is the best kind, being light and with a rough surface 
suitable for the rooting of plants, etc. ; and if fancy forms are 
desired (bridge- work, etc.), the pumice-stone can be cut quite easily 
to the desired shapes. The plants are rooted in the sand and the 
vessel left at rest for a week for the plants to vegetate. The fol- 
lowing plants will be found useful : Utricularia inflata, utricu- 



224 HOUSEHOLD HINTS. 



laria vulgaris, myriophyllum spicatnrriy anarcharis Canadensis, and 
Jiottonia iuflata. 

In obtaining plants, procure all the roots and see that they are 
well rooted. If fungus should form, add snails {planorbis trivol- 
vis) ; they will completely destroy it. After the plants are well 
started, add the shells and amphibious animals. The following 
shells will be found desirable : Planorhis trivoldis,physa hetero- 
strapha, unio complanatus. Many shells are not needed. Snails 
act the part of scavengers ; and where the different elements of 
an aquarium are rightly iDalanced, two or more snails will be 
found sufficient. 

If amphibious animals are introduced, the rock- work must ex- 
tend above the surface of the water, or a float of some kind must 
be substituted. It is impossible for them to live under water all 
the time, and they would die without some such arrangement. 

The turtles claim first rank. The enys punctata, or spotted 
water-turtle, and the chrysemys picta, or painted water-turtle, 
will be found to be the best for the aquarium, and should be pro- 
cured when very young, as they are very destructive when old. 
The tritons (triton tigrinus, triton niger), the red salamander, the 
cray-fish {astacus Bartoni), are all suitable, and present a very 
odd and yet a very natural look to the aquarium. 

In selecting the fishes, a few only thrive in confinement. 
Among these, and the first, is the gold-fish. He can live for 
months without introduced food, and is, without comparison, the 
most hardy, standing remarkable changes in the temperature ; and 
he is the most gaudy and attractive. A large number of the 
fishes prey upon each other, and will only do for the aquarium 
when in the young state. Among these may be mentioned pomo- 
t is vulgaris, or sun-fish, esox reticulatus, or common pickerel, and 
perca florescens, or yellow perch. The leuciscuspyymoius, or rock- 
fish, is a great addition, and is found very plentifully in our 
streams. The pimelodus atrarius, or common black catfish, is 
another worthy of a place. So also is the hydrargia diaphana, 
or transparent minnow. But few fish can live in an aquarium, 
and the needless crowding together, so often seen, is very hurtful 
to health, and causes sound, strong fish in a short time to become 
weak and poor. The great difficulty in keeping an aquarium is to 
secure enough oxygen for the fish. To a slight degree, it is the 
duty of the plants to supply this ; but if too much vegetation be 
present, decomposition takes place and ruin follows. It has been 
demonstrated that only a small amount is necessary to absorb the 
carbonic acid given off by the fish and amphibians ; consequently, 
if the water be daily aerated with a syringe, it will absorb an 
abundant supply of oxygen for the animal life, and the trouble 
arising from the decay of much vegetable matter will be lessened 
or altogether avoided. 

Aquarium, To mend broken glass of an. — Fasten a strip of 
glass over the crack, inside the aquarium, using for a cement 
white shellac dissolved in ^ its weight of Venice turpentine. 

Awnings, Waterproofing. — Dip first in a solution contain- 
ing 20 per cent soap, and afterwards in another solution contain- 
ing the same percentage of copper. Wash afterwards. 



HOUSEHOLD HINTS. 225 

Benzole, Necessity of care in use of. — Benzole is often em- 
ployed for removing grease-spots. It is highly volatile and in- 
flammable ; so that the contents of a 4-oz. phial, if overturned, 
will render the air of a moderate- sized room highly explosive. 
Never handle it near a fire or light, as the flame, igniting the 
vapor from an uncorked bottle, will leap over to the latter, often 
over a distance of several feet. 

Bites, Rattlesnake, Remedy for. — The following is used by 
soldiers on the plains, and is said to be efficacious : Iodide of 
potassium, 4 grains ; corrosive sublimate, 2 grains ; bromine, 5 
drachms. Ten drops, diluted with a tablespoonful or two of 
brandy, wine, or whisky, is the dose, to be repeated if necessary. 
Keep in a well- stoppered phial. 

Boot Jelly and Shirt Coffee. — Some time ago, Dr. 
Vander Weyde, of New- York City, regaled some friends not 
merely with boot jelly, but with shirt coffee, and the repast was 
pronounced by all partakers excellent. The doctor tells us that 
he made the jelly by first cleaning the boot, and subsequently 
boiling it with soda, under a pressure of about two atmospheres. 
The tannic acid in the leather, combined with salt, made tannate 
of soda, and the gelatin rose to the top, whence it was removed 
and dried. From this last, with suitable flavoring material, the 
jelly was readily concocted. The shirt coffee, which we inciden- 
tally mentioned above, was sweetened with cuff and collar sugar, 
both coffee and sugar being produced in the same way. The 
linen (after, of course, w^ashing) was treated with nitric acid, 
which, acting on the lignite contained in the fibre, produced glu- 
cose, or grape sugar. This, roasted, made an excellent imitation 
coffee, which an addition of unroasted glucose readily sweetened. 

Boots, Waterproofing. — Use a piece of paraffine candle 
about the size of a nut, dissolved in lard-oil at 140° Fahr. Apply 
once a month. 

Boots, To stop squeaking of. — Drive a peg into the middle of 
the sole. 

Boots, Wet. — When the boots are taken off, fill them quite 
full with dry oats. This grain has a ^reat fondness for damp, 
and will rapidly absorb the least vestige of it from the wet 
leather. As it quickly and completely takes up the moisture, it 
swells and fills the boot with a tightly-fitting last, keeping its 
form good, and drying the leather without hardening it. In the 
morning, shake out the oats and hang them in a bag near the 
fire to dry, ready for the next wet night ; draw on the boots, and 
go happily and comfortably about the day's work. 

Bottles containing Resinous Solutions, To clean. — Wash 
with caustic alkaline lyes and rinse with alcohol ; if they have 
held essential oils, wash with sulphuric acid and rinse with 
water. 

BOTTLFS, Sealing. — Gelatine mixed with glycerine is used for 
this purpose. This is liquid while hot, but an elastic solid when 
cold. 

Bottles, To cut in two. — Turn the bottle as evenly as possi- 
ble over a low gaslight flame for about 10 minutes ; then dip 



226 HOUSEHOLD HINTS. 

steadily in water, and tlie sudden cooling will cause a regular 
crack to encircle the side at the heated place, allowing the por- 
tions to be easily separated. 

Bottles, To prevent breakage in packing. — Slip rubber rings 
over them. 

Burns, Remedy for. — White lead rubbed to a paste in linseed- 
oil. Another good remedy is as follows : Take the best white 
glue (extra), 15 ozs. ; break it into small pieces, add to it 2 
pints cold water, and allow it to become soft. Then melt it on 
a water-bath, add to it 2 fluid ounces glycerine and 6 drachms 
carbolic acid, and continue the heat on the water-bath until a 
glossy, tough skin begins to form over the surface in the inter- 
vals of stirring. The mixture may be used at once, after the 
glue is melted and the glycerine and carbolic acid are added ; but 
when time allows, it is advisable to get rid of a little more of the 
water, until the proper point is reached. On cooling, this mix- 
ture hardens to an elastic mass, covered with a shining parch- 
ment-like skin, and may be kept for any time. When using it, 
it is placed for a few minutes on the water-bath until sufficiently 
liquid lor application. (It should ba quite fluid.) Should it at any 
time require too high a heat to become fluid, this may be corrected 
by adding a little water. It is applied by means of a broad 
brush, and forms in about two minutes a shininof, smooth, flexi- 
ble, and nearly transparent skin. It may be kept for any time, 
without spoiling, in delf or earthen dishes or pots turned upside 
down. 

Butter, Rancid, To purify. — Melt in twice its weight of boil- 
ing water and shake well. Pour the melted butter into ice- 
water, to regain its consistence. Another : Wash in good new 
milk, in which the butyric acid, which causes the rancidity, is 
freely soluble. Wash afterward in cold spring-water. Another 
plan is to beat up i lb. good fresh lime in a pail of water. Allow 
it to stand for an hour, until the impurities have settled. Then 
pour off the clear portion, and wash the butter in that. 

Caps, Paper, To make. — Provide a sheet of moderately thick 
brown paper, size from 18 inches to 2 feet, shape as in Fig. 1. 
Smooth it out perfectly flat, and double over as in Fig. 2. Turn 
it round with the fold from you, and mark the exact middle of 
the piece at A, Fig. 3. Then bring down both corners, and 
measure off on the edge B from the point A, Fig. 3, a distance 
equal to i the circumference of your head. Mark the point. 
Now turn the paper over so that the under side will be upper- 
most, and bend the apex of the triangle back from the point just 
marked, as in Fig. 4. Fold over the sides. Figs. 5 and 6, and 
with scissors cut off the portion, C, below the dotted line, 
and also the points of the two lower corners of the pieces just 
bent over. Next unfold the paper; spread it out flat : you will 
find a square marked in the middle, and creases leading there- 
from to the corners of the paper. Double up the material on 
these creases, so as to bring up the paper as sides of a box, of 
which the middle square is the bottom, as in Fig. 7. Smooth the 
folds flat, and your work will appear as in Fig. 8. Lastly, turn 



HOUSEHOLD HINTS. 



227 




MAKING PAPER. CAPS. 



up the edges of tlie box all around twice, folding the paper on 
itself. Your cap is then complete, and if the measurement di- 
rected above was correctly made, it will exactly fit your head. 

Calico, To wash, without fading. — Infuse 3 gills of salt in 4 
quarts of water. Put in the calico while the solution is hot, and 
leave until the latter is cold. It is said that in this way the 
colors are rendered permanent, and will not fade by subsequent 
washing. 

Carpets, To prevent moth in, — Wash the floor before laying 
with spirits of turpentine or benzine. Do not do this with a fire 
in the room, or with any matches or lights near. 

Casks.— Rancid butter, pork, and lard casks may be purified 
by burning straw or shavings in them. 



228 HOUSEHOLD HINTS. 

Cellars, Dry-rot in. — This, in cellar timbers, can be pre- 
vented by coating the wood with whitewash to which has been 
added enough copperas to give the mixture a pale-yellow hue. 

Cellars, Testing, for dampness. — Provide yourself with a 
thermometer, a glass tumbler filled with water, and a piece of 
ice ; then notice how low your thermometer, when placed in the 
tumbler, has to sink before any moisture begins to show itself on 
the outside of the vessel of cold water. The lower the tempera- 
ture to which the thermometer has to sink before moisture is 
precipitated, the less there is of it in the moisture of the cellar. 

Chair-Bottoms, To restore elasticity of cane. — Turn the 
chair-bottom upward, and with hot water and a sponge wash the 
cane ; work well, so that it is well soaked ; should it be dirty, 
use soap ; let it dry in the air, and it will be as tight and firm as 
new, provided none of the canes are broken. 

Chapped Hands. — Rub over with fine soap, and, while the 
lather is still on, scrub the hands thoroughly with about a table- 
spoonful of Indian meal. Rinse with tepid water, dry thorough- 
ly, and wet again with warm water containing a quarter of a tea- 
spoonful of pure glycerine. Dry without wiping, rubbing the 
hands together until all the water has evaporated. Do this at 
night before retiring, and the effect will be apparent by morn- 
ing. 

Chest- Protector, A simple. — A folded newspaper placed 
over the chest inside the vest, on going out during raw spring 
weather, constitutes an excellent protector for the lungs. 

Chicken FEx\thers, Utilizing. — Cut the plume portions of the 
feathers from the stem, by means of ordinary hand-scissors. The 
former are placed in quantities in a coarse bag, w^iich, when full, 
is closed and subjected to a thorough kneading with the hands. 
At the end of five minutes, the feathers become disaggregated 
and felted together, forming a down perfectly homogeneous and 
of great lightness. It is even lighter than natural eider-down, 
because the latter contains the rilDS of the feathers, which give 
extra weight. About 1.6 troy ounces of this down can be ob- 
tained from the feathers of an ordinary -sized pullet. It is sug- 
gested that, through the winter, children might collect all the 
feathers about a farm, and cut the ribs out as we have stated. 
By the spring-time, a large quantity of down would be prepared, 
which could be disposed of to upholsterers, or employed for do- 
mestic uses. Goose-feathers may be treated in a similar manner, 
and thus two thirds of the product of the bird utilized, instead of 
only about one fifth, as is at present the case. The chicken-down 
is said to form a beautiful cloth when woven. For about a square 
yard of the material, a pound and a half of down is required. 
The fabric is said to be almost indestructible, as, in place of fray- 
ing or wearing out at folds, it only seems to felt the tighter. It 
takes dye readily, and is thoroughly water-proof. 

Chicory, Determination of, in ground coffee. — Gently strew 
the powder upon the surface of cold water. Chicory, burnt sugar, 
etc., contain no oil, and their caramel is very quickly extracted 
by the water, with production of a brown color, while the parti- 



HOUSEHOLD HINTS. 229 

cles themselves rapidly sink to the bottom of the water. On 
stirring the liquid, co&ee becomes tolerably uniformly diffused 
without sensibly coloring the water, while chicory and other 
sweet roots quickly give a dark-brown turbid infusion. Roasted 
cereals do not give so distinct a color. 

Chimneys, Burning, Prevention of. — The soot in the chimney 
can not burn, except as the fire of the stove is communicated to 
it through the pipe. If the pipe, therefore, be kept clean and free 
from soot, and the damper in the stove always closed, the chim- 
ney will never burn out. To free the pipe of soot, take the 
stove-handle or any convenient implement, and rap the pipe 
smartly on all sides from top to bottom. The soot will fall into 
the stove and be harmlessly consumed, or it can be removed in 
the usual way. 

If there be a horizontal pipe, this should be taken down twice 
a year and thoroughly cleaned. Or, if the pipe be only a few 
feet in length, and the arrangements will admit of it, provide 
the horizontal pipe with a permanent scraper, as follows : To the 
end of a stout wire, a few inches longer than the pipe, attach a 
small segment of a disk of sheet-iron, at right angles to the wire. 
Remove the elbow, and thrust the scraper into the pipe. Pass the 
other end of the wire through a hole punched in the elbow, loop 
the end of the wire for a handle, and replace the elbow. After 
first rapping the pipe, the soot can all be drawn out and let fall 
into the stove. Clean the pipe thus as often as once a fortnight 
during cold weather. 

Chimneys, Smoky stove or range. — To prevent smoking, use 
a screen or blower of fine wire gauze, from 36 to 40 wires to the 
inch, immediately in front of the fire and about two inches there- 
from. 

Chimneys, Sooty, Cure for. — Plaster the inside with salt 
mortar. The proportions used are 1 peck salt added, while tem- 
pering, to 8 pecks mortar. Chimneys thus treated have re- 
m.ained perfectly clean for fifteen years. 

Clothes, Fire-proof wash for. — Four parts borax and 3 parts 
Epsom salts, mixed with 3 or 4 parts warm water to 1 part of the 
combined substances, is an excellent fire-proof wash for clothes. 
It should be used immediately after preparation. 

China and Glass Ware, Care of. — One of the most impor- 
tant things is to season glass and china to sudden change of tem- 
perature, so that they will remain sound after exposure to sudden 
heat and cold. This is best done by placing the articles in cold 
water, which must gradually be brought to the boiling point, 
and then allowed to cool very slowly, taking several hours to do 
it. The commoner the materials, the more care in this respect 
is required. All china that has any gilding upon it may on no 
account be rubbed with a cloth of any kind, but merely rinsed 
first in hot and afterward in cold water, and then left to drain 
till dry. It may be rubbed with a soft wash-leather and a little 
dry whiting ; but this operation must not be repeated more than 
once a year, otherwise the gold will most certainly be rubbed off, 
and the china spoilt. When the plates, etc., are put away in 
the china closet, pieces of paper should be placed between them 



2aO HOUSEHOLD HINTS. 

to prevent scratclies on the glaze or painting, as the bottom of 
all ware has little particles of sand adhering to it, picked up 
from the oven wherein it was glazed. The china closet should 
be in a dry situation, as a damp closet will soon tarnish the gild- 
ing of the best crockery. In a common dinner-service, it is a 
great evil to make the plates too hot, as it invariably cracks the 
glaze on the surface, if not the plate itself. The fact is, when 
the glaze is injured, every time the ''things" are washed the 
water gets to the interior, swells the porous clay, and makes the 
whole fabric rotten. In this condition they will also absorb 
grease ; and when exposed to further heat, the grease makes the 
dishes brown and discolored. If an old, ill-used dish be made 
very hot indeed, a teaspoonful of fat will be seen to exude from 
the minute fissures upon its surface. These latter remarks apply 
more particularly to common wares. 

As a rule, warm water and a soft cloth are all that is required 
to keep glass in good condition ; but water-bottles and wine-de- 
canters, in order to keep them bright, must be rinsed out with a 
little muriatic acid, which is the best substance for removing the 
''fur" which collects in them. This acid is far better than 
ashes, sand, or shot ; for the ashes and sand scratch the glass, 
and if any shot is left in by accident the lead is poisonous. 

Richly-cut glass must be cleaned and polished with a soft 
brush, upon which a very little fine chalk or whiting is put ; by 
this means the lustre and brilliancy are preserved. 

Cider- Stains. — These may be removed by lemon -juice or 
citric acid. 

Cinders, Sifting. — To insure servants doing this, and to pre- 
vent vegetable refuse being thrown into the ash-barrel, provide 
a grated cover for the latter, which secure by a padlock to pre- 
vent removal. 

Cisterns, defining. — This should be done just before warm 
weather sets in, and should be done every year. 

Clinkers, To remove, from stoves or fire-brick. —Put in about 
half a peck of oyster-shells on top of a bright fire. This may 
need repeating. 

Clothing, Winter. — Sufficient clothing should be worn to 
keep off a feeling of chilliness when about usual avocations. 
Less than that subjects one to an attack of dangerous pneumonia 
at any day or hour. More than that oppresses. Steadily aim, 
by all possible ways and means, to keep off a feeling of chilli- 
ness, which always indicates that a cold has been taken. 

Clothes, Protective power of. — Clothes protect the body, by 
allowing through their interstices such ventilation that the 
nervous system may not be sensible to extremes in changes of 
temperature. Dr. Pettenkofer states that equal surfaces of vari- 
ous materials are permeated by air as follows, fiannel being taken 
as ICO : Linen of medium fineness, 58 ; silk, 40 ; buckskin, 58 ; 
tanned leather, 1 ; chamois leather, 51. 

Clothes, Renovating old. — Two ozs. common tobacco boiled 
in 1 gallon water is used by the Chatham-street dealers for reno- 
vating old clothes. The stuff is rubbed on with a stiff brush. 



HOUSEHOLD HINTS. 281 

The goods are nicely cleaned, and, strange to add, no tobacco 
smell remains. 

Clothes, Washing compound for. — The German washerwo- 
men use a mixture of 2 ozs. turpentine and 1 oz. spirits of 
ammonia well mixed together.- This is put into a bucket of 
warm water, in which ^ lb. soap has been dissolved. The 
clothes are immersed for 24 hours and then washed. The cleans- 
ing is said to be greatly quickened, and 2 or 3 rinsings in cold 
water remove the turpentine smell. 

Cockroaches, To drive away. — Poke-root {'Phytolacca de- 
candra), sliced thin and laid about a house, will destroy cock- 
roaches quicker than any other poison. It never fails. Another 
way of preparing the root is to boil 1 oz. in 1 pint water, until all 
the strength is extracted. Mix with molasses, and spread on 
plates in the localities infested by the insects. 

COEK, To remove a, when pushed in a bottle. — When a cork 
gets pushed down into the neck of a bottle, insert a loop of strong 
twine and engage the cork in any direction most convenient. 
Then give a strong pull, and the cork will generally yield suffi- 
ciently to be withdrawn. 

Corn, To can green. — Dissolve 2^ ozs. tartaric acid in a pint 
of water. Of this solution, use 1 tablespoonful to every pint of 
corn while the corn is at boiling heat. When opened for use, add 
1 teaspoonful soda to every 3 pints of corn. 

Cushions, Stuffing. — Flaxseed and tallow are used in Germany 
as a stuffing for cushions. One part of tallow to 10 parts of flax- 
seed are employed, the mobility of the greased seed rendering 
the cushion very soft and pliable. 

Disinfectant for the Breath, etc. — A very weak solution of 
permanganate of potash is an excellent disinfectant for light pur- 
poses, such as rinsing spittoons, neutralizing the taint of diseased 
roots of teeth, cleansing the feet, and keeping the breath from 
the odor of tobacco-smoke. Permanganate is not poisonous. 

Engravings, To clean mildewed or stained. — Moisten the 
paper carefully, and suspend it in a large vessel partially filled 
with ozone. To evolve the latter, the simplest way is to clean 
pieces of phosphorus and place them, half covered with water, in 
the bottom of the jar in which the pictures are hung. On a large 
scale, a Ruhmkorff coil, giving a constant discharge of electricity, 
would be preferable. 

Eye, To remove substances from the. — Take hold of the 
upper eyelid, near its angles, with the index-finger and thumb of 
each hand. Draw it gently forward, and as low down as possible 
over the lower eyelid, and retain it in this position for about a 
minute, taking care to prevent the tears from flowing out. 
When, at the end of this time, you allow the eyelid to resume its 
place, a flood of tears washes out the foreign body, which will be 
found adhering to, or near, the lower eyelid. 

Fermentation of Food. —This should be guarded against as 
the warm weather approaches. This action is always liable to 
cooked vegetables when set aside. Instead of warming up cold 
messes, it is better to scald them. 



232 HOUSEHOLD HINTS. 

Bugs, Fleas, etc., To destroy. — This mixture, which has been 
patented in France, consists of 80 parts of bisulphide of carbon 
and 20 parts of essence of petroleum. 

Floors, Cheap paint for. — This is made of 5 lbs. French ochre, 
i lb. glue, and 1 gallon hot water. When well dried, apply one 
or two coats of linseed-oil. 

Floors, Oak stain for. — An oaken color can be given to new 
pine floors and tables by washing them in a solution of copperas 
dissolved in strong lye, a pound of the former to a gallon of the 
latter. When dry, this should be oiled, and it will look well for 
a year or two ; then renew the oiling. 

Floor Wax, Preparation of. — Heat to boiling 2 ozs. of pearl- 
ash, 10 ozs. of wax, and ^ pint of water. Stir frequently, 
until a thick fluid mass is formed from which, upon removal 
from the fire, no watery liquid separates out. Add boiling water 
cautiously, until no watery drops are distinguishable. Place on 
the fire again, but do not allow to boil, and add by degrees 8 or 9 
pints of water, stirring constantly. 

Earthenware, Porous, To clean. — This often becomes foul 
with organic matter when used to hold water. Use 1 oz. mu- 
riatic acid, rubbed on exterior and interior with a piece of flan- 
nel. Wash afterward with hot water. 

Eggs, To preserve. — Mix together in a tub or vessel 1 bushel 
of quicklime, 82 ozs. of salt, 8 ozs. cream of tartar, with as much 
water as will reduce the composition to a sufiicient consistence to 
float an egg. It is said that this treatment will preserve the eggs 
perfectly sound for two years at least. 

Flowers, Preserving. — The flowers must be carefully sur- 
rounded by perfectly dry, fine sand, in such a manner that they 
will hold their form, the pressure of the sand upon all surfaces 
being alike. Any fine clean sand will answer ; it should be sifted 
to remove all coarse particles, and then washed in successive 
waters until dust and all earthy and clayey matters are washed 
away, and the last waters when poured off are perfectly clear. 
The sand is then to be dried and then placed over a fire in a 
proper vessel, until quite hot, hotter than the hand can bear, 
and when cool it will be fit to use. After heating, it should be 
used at once, before it can absorb moisture from the air. Good 
results have been obtained by taking a clean, thoroughly dry 
flower-pot, the hole in the bottom of which was stopped by a 
cork. This was filled a third full of the dry sand, the flowers 
set carefully in the sand, and then more sand slowly added, so as 
to surround and cover the flowers inside and out, and set in a 
warm place. At the end of 24 hours, the cork was removed 
from the hole in the flower-pot, and the sand allowed to run out 
in a small and gentle stream. The flowers were left in the pot, 
perfectly dry. 

Fly-Paper, Adhesive. — Smear paper with a mixture of mo- 
lasses and linseed-oil. 

Fragments of Metal, Extracting, from the flesh.— A simple 
and usually successful mode of extracting a needle, or any piece 
of steel or iron broken off in the flesh, is accomplished by the 



HOUSEHOLD HINTS. 233 

application of a simple pocket magnet. Iron filings have a way 
of imbedding themselves in the eye which defies almost every 
ordinary means for their extraction. For their removal, a small, 
blunt, pointed bar of steel, well magnetized, will be found excel- 
lent, and we should recommend that workmen liable to such in- 
juries keep such an instrument about tliem. It would be a good 
plan to insert such a bar in a penknife, in a manner similar to a 
blade. 

Fruit, Canning. — The following table for boiling fruit in cans 
will doubtless prove useful. The first figure after the name of 
the fruit refers to time of boiling in minutes, the second to 
ounces of sugar to the quart : Cherries, 5, 6 ; raspberries, 6, 4 ; 
blackberries, 6, 6 ; gooseberries, 8, 8 ; currants, 6, 8 ; grapes, 10, 
8 ; plums, 10, 8 ; peaches (whole), 15, 4; peaches (halves), 8, 4; 
pears (whole), 30, 8 ; crab-apples, 25, 8 ; quinces (sliced), 15, 10 ; 
tomatoes, 30, none ; beans and peas, 3 to 4 hours. 

Furnace Heat, To moisten. — Dry furnace heat, productive of 
throat and lung diseases, may be moistened by hanging a wet 
towel in front of the register, the lower edge of the towel being 
allowed to dip in a shallow vessel of water. 

Furnace, To prevent rust in a. — Throw some quicklime loose- 
ly on a board, and place inside the furnace. 

. Furniture, Refinishing oiled or varnished. — Oiled furniture, 
scratched or marred, may be restored by rubbing with a woolen 
rag dipped in boiled linseed-oil. Varnished, by similarly rubbing 
with a varnish of shellac dissolved in alcohol. 

Fabrics, To make uninfiammable. — The lightest materials are 
rendered uninflammable by washing in a concentrated neutral so- 
lution of tungstate of soda, diluted with about one third of water, 
and then mixed with 3 per cent of phosphate of soda. 

Feet, Frosted. — These can be relieved of soreness by bathing 
in a weak solution of alum. 

Ferns, Ornaments made of. — Handsome ornaments can be 
made by mounting fern-leaves on glass. The leaves must first 
be dyed or colored. They are then arranged on the mirror ac- 
cording to fancy. A butterfly or two may be added. Then a 
sheet of clear glass of the same size is placed on top, and the two 
sheets secured together at the edges and placed in a frame. 

Fire- Alarm, A simple and good. — An old gun loaded with a 
heavy charge of powder, and hung near the rafters in a barn, or 
in any dangerous locality about the house, makes an excellent 
fire-alarm. The explosion is caused by the heat. 

Fire, Extinguishing. — A solution of pearlash in water, thrown 
upon a fire, extinguishes it instantly ; the proportion is 4 ozs., 
dissolved in hot water, and then poured into a bucket of common 
water. 

Fires, Kerosene. — Never try to extinguish a kerosene fire with 
water. Smother the flames with blankets or rugs. 

Fire, Precautions in case of. — Keep all doors and windows of 
the structure closed until the firemen come ; put a wet cloth over 
the mouth and get down on all fours in a smoky room ; open the 



234 HOUSEHOLD HINTS. 

upper part of the window to get the smoke out. If in a tlieatre, 
keep cool. Descend ladders with a regular step, to prevent vibra- 
tion. If kerosene just purchased can be made to burn in a sau- 
cer by i^nifmg witli a match, throw it away. Put wirew^ork over 
gaslighfs in show-windows ; sprinkle sand instead of sawdust on 
floors of oil stores ; keep shavings and kindling-wood away from 
steam-boilers, and greasy rags from lofts, cupboards, boxes, etc. ; 
see that all stove-pipes enter well in the chimney, and that all 
lights and fires are out before retiring or leaving place of busi- 
ness ; keep matches in metal or earthen vessels, and out of the 
reach of children ; and provide a piece of stout rope, long enough 
to reach the groiind, in every chamber. Neither admit any one, 
if the house be on fire, except police, firemen, or known neigh- 
bors ; nor swing lighted gas-brackets against the wall ; nor leave 
small children in a room where there are matches or an open fire; 
nor deposit ashes in a wooden box or on the floor ; nor use a light 
in examining the gas-meter. Never leave clothes near the fire- 
place to dry ; nor smoke or read in bed by candle or lamp light ; 
nor put kindling-wood to dry on top of the stove ; nor take a 
light into a closet ; nor pour out liquor near an open light ; 
nor keep burning or other inflammable fluids in a room where 
there is a fire ; nor allow smoking about barns or warehouses. 

Fires, Usual causes of. — Churches and lecture-rooms of all 
descriptions. — Hot air, hot water and steam pipes, and furnaces 
and stoves. Sticking candles against coflfins in vaults. Christ- 
mas and other decorations around or too near gas-fittings, fires, 
or lights. Sparks falling upon birds' nests in spires and belfries. 

Curriers and workers in leather. — Lime slaked by rain. Sparks 
from foul flues and furnaces passing through opening and pro- 
jecting eaves of drying-rooms. Friction of machinery in bark- 
mills. Timber, coals, shavings of wood, and leather too near flues. 
Drying stoves and furnaces. Spontaneous ignition. Smoking in 
bark and other rooms. 

Drapers, tailors, makers up. and vendors of male and female at- 
tire. — Working late, being tired and falling asleep, or becoming 
careless too near fires and lights. Unprotected and swinging gas- 
brackets. Crinolines coming in contact with fire in or>3n fire- 
places. Light, pendent goods being blown, by the 0])ening and 
shutting of doors or by concussions or drafts, into unprotected 
lights. Groods hung on lines increase the risk in various ways, 
such as conveying the flame from one end of a room to the 
other, and, when the line breaks down, making three separate 
fires, one at each end and one in the middle at the same time, 
thus originating three distinct fires for each line. Cuttings left 
carelessly about. Using lights while intoxicated, especially by 
tailors' work-people. Ironing-stoves, hot plates, smoothing-irons, 
etc. , too near and sometimes on timber and goods. Smoking- to- 
bacco, and matches for lighting it. 

Engineering works, and workers in metal of all descriptions. — 
Sparks from striking hot metal, hot metal castings, etc. , left too 
near timber. Heat from furnaces, forges, and smiths' hearths and 
flues. Friction of machinery. Japanners' stoves overheated or de- 
fective. Accidents with melted or hot metal. Explosions of blast- 
furnaces. Spontaneous ignition of oily waste, moulders' lamp, and 



HOUSEHOLD HINTS. 235 

Other blacks ; sawdust or sweepings and oil ; spontaneous heating 
of iron turnings, etc., when mixed with water and oil. 

Farming -stock, stables, hay, grain, or flour stores of ad descrip- 
tions. — Stacking hay while green. Sparks from passing locomo- 
tives, etc. Sparks from steam thrashing machines. Sticking 
candles against walls and timber in barns and stables. Vagrants 
smoking in stables. Vagrants beino;' refused alms. Fire-arms 
used near farming-stock, such as haystacks, etc. 

Makers of gunpowder, fireworks, lucifer matches, and explosive 
compounds. — Overheating of drying-stoves and explosive mix- 
tures. Dropping lucifers. Unprotected lights. Smoking. Leav- 
ing phosphorus uncovered with water. Friction and percussion 
from nails in boots. Sparks passing through broken windows. 
The sun's rays being concentrated through bull's-eyes, knots, 
etc., in glass. Defective casks containing gunpowder or other 
explosive materials. Spontaneous ignition of red fire and such- 
like compositions. Carelessness in the supervision of young 
children employed. Shavings and chips too near fires and lights. 

Gas-works. — Hot coke near timber, etc. Seeking for an escape 
with unprotected lights. Timber too near furnaces, retorts, etc. 
Lime slaked by rain. Defective fittings and appliances. Spon- 
taneous ignition of coals. 

Hat manufactories. — Boiling shellac. Hot irons left on timber 
and other inflammable things. Defective drying and other stoves. 
Smoking tobacco. 

Fishing, Comfortable. — A plan practiced on the Western 
lakes in winter consists in having a small house, built on run- 
ners like those of a sled, in which is placed a small stove, while 
in the floor a small aperture is left through which to drop the 
lines. Holes are cut in the ice, the houses are moved over them, 
and the fishermen sit by a warm stove while drawing in the fish. 

Fish, Gold, Treatment of. — Seth Green says this as to the 
proper care and treatment of gold-fish : *' Never take the fish in 
your hand. If the aqaarium needs cleaning, make a net of 
mosquito-netting and take the fish out in it. There are many 
gold-fish killed by handling. Keep your aquarium clean, so 
that the water looks as clear as crystal. Watch the fish a little, 
and you will find out when they are all right. Feed them all 
they will eat and any thing they will eat — worms, meat, fish- 
wafer, or fish-spawn. Take great care that you take all that they 
do not eat out of the aquarium ; any decayed meat or vegetable 
in water has the same smell to fish that it has to you in air. If 
your gold-fish die, it is attributable, as a rule, to one of three 
causes — handling, starvation, or bad water." 

Fishing-Lines, To water- proof. — Apply a mixture of 2 parts 
boiled linseed-oil and 1 part gold size ; expose to the air, and 
dry. 

Flannels, To wash. — Take soft water, as warm as you can 
bear your hands in. Make a strong suds, well blued. In wash- 
ing fine fiannels, wet but one piece at a time ; soap the dirty 
spots and rub with the hands, as washboards full the flannels. 
When half clean, add three times as much blue as for cotton 
clothes. Use plenty of soap. When clean, have ready a rinse of 



236 HOUSEHOLD HINTS. 

tlie same temperature as the suds, rinse well, wring tight, shake 
briskly for a lew minutes, hang out in a gentle breeze. When 
nearly dry, roll smooth and tight for an hour or two. Press with 
a moderately hot iron. If embroidered, press on the wrong side. 
Flannels washed in this way will look white and clean when 
worn out, and the quality will look better than when new. 

Garbage, To dispose of. — When not fed to pigs, the best way 
to get rid of kitchen refuse is to burn it in the range or stove. 

Gas Escaping, To detect. — To find the leak, first see that no 
burners have been left accidentally turned on. This is often the 
case where the cock has no stop, and is caused by the cock being 
partially turned around again so as to open the vent. Imperfect 
stop-cocks for this reason are dangerous, and should be promptly 
repaired. Try all the joints of the gas-fittings, by bringing a 
lighted match near them, to ignite the escaping gas if any there 
be. In case it is found by the sense of smell that the gas is 
escaping either within the floor or walls, do not on any account 
apply a match near a crevice. Turn off the <2:as at the metre, 
and send for a gas-fitter at once. In ordinary leaks, the burner 
or joint should be unscrewed, and white lead or common bar- 
soap rubbed in the threads before screwing home again. 

Gas-Light, Average prices of, in the United States. — Maine, 
$3.87. New-Hampshire, $3.9(). Vermont, $4.80. Massachusetts, 
$3.86. Rhode-Island, $3.35. Connecticut, $4.03. New-York, $3.88. 
New- Jersey, $3.80. Pennsylvania, $3.46. Delaware, $3.95. Mary- 
land, $3.59. Dist. of Columbia, $3.16. Virginia, $3.89. West- 
Virginia, $3.11. North-Carolina, $6.67. South-Carolina, $3.80. 
Georgia, $5.07. Florida, $8.00. Alabama, $4.83. Mississippi, 
$5.25. Michigan, $3.43. Wisconsin, $3.87. Ohio, $3.32. Indiana, 
$3.54. Illinois, $3.87. Kentucky, $3.92. Tennessee, $4.06. Min- 
nesota, $4.31. Iowa, $4.52. Missouri, $3.95. Arkansas, $5.00. 
Louisiana, $4.50. Texas, $5.75. Kansas, $4.55. Colorado, $5.00. 
Utah, $4.00. California, $6.11. 

Total average net price of gas in the United States, $4.32^. 

Gilt Fkames, To restore. — Rub with a sponge moistened in 
urine or turpentine. 

Glass, To break in any required form. — Make a small notch, 
by means of a file, on the edge of a piece of glass ; then make 
the end of a tobacco-pipe, or a rod of iron about the same size, 
red-hot in the fire, apply the hot iron to the notch, and draw it 
slowly along the surface of the glass in any direction you 
please ; a crack will be made in the glass and will follow the di- 
rection of the iron. Round glass bottles and flasks may be cut in 
the middle by wrapping round them a worsted thread dipped in 
spirits of turpentine, and setting it on fire when fastened on the 
glass. 

Glass Jars, To cut. — Fill the jar with lard-qil to where you 
want to cut the jar ; then heat an iron rod or bar to red heat, im- 
merse it in the oil ; the unequal expansion will check the jar all 
round at the surface of the oil, and you can lift off the top part. 

Glass, To cut without a diamond. — Hold it level under water, 
and, with a pair of scissors, clip it away by small bits from the 
edges. 



HOUSEHOLD HINTS. 237 

Grease-Spots on Clothing, To remove.~In using benzole or 
turpentine, people make the mistake of wetting the cloth with 
the turpentine and then rubbing it with a sponge or piece of 
cloth. The only way to radically remove grease-spots is to place 
solt blotting-paper beneath and on top of the grease-spot, which 
spot has first been thoroughly saturated with the benzole, and then 
well pressed. The fat gets now dissolved and absorbed by the 
paper, and entirely removed from the clothing. 

Hams, Pickle for curing.— An excellent, well-recommended 
pickle for curing hams is made of 1| lbs. of salt, ^ lb. of sugar 
i oz. of saltpetre, and i oz. of potash. Boil all together till the 
dirt from the sugar has risen to the top and is skimmed. Pour 
it over the meat, and leave the latter in the solution for 4 or 5 
weeks. 

Hearths, Soapstone, To wash.— Use pure water, and then 
rub with powdered marble or soapstone put on with a piece of 
the same stone. 

Hearths, To clean gray marble.— Rub with linseed-oil, and no 
spots will show. 

Ice- Water, To preserve.— Make a hat-shaped cover of two 
thicknesses of paper, with cotton batting ^ inch thick between. 
Place over the entire pitcher 

Incubator, A cheap.— One of the easiest constructed forms 
of incubator for the artificial hatching of eggs <!onsists simply of 
a cask well buried in a manure-heap. In the bottom of the cask 
place one or two sieves to hold the eggs, and make a door in the 
side for the removal of chickens, etc. A pane of glass may also 
be inserted either in the door or at any convenient point for view- 
ing the interior. In the head, which should be removable, make 
an opening provided with a sliding cover, for regulating the size 
of the aperture, as may be necessary. Form a bed of fresh 
manure about 1 ft. thick (after bedding) and 6 ft. square. On 
this set the cask, and pack more manure around the latter until 
flush with the top. Now take off the head or cover and place a 
thermometer on one of the sieves. Replace the cover. The 
natural heat of the manure will warm the interior of the cask. 
When the temperature reaches 104° (seen by the thermometer), 
place the eggs on the sieves. The hatching process then begins, 
and lasts the usual time. Care should be taken to turn the eggs 
over once a day, and to allow them to cool slightly, thus imitat- 
ing the natural habit of the hen when she leaves her nest in 
search of food. The temperature of the interior is kept uniform 
at 104° by removing manure from the side of the cask to lessen 
the heat, or by substituting manure fresh from the stables in 
place of the older material, in order to increase the warmth. 

After the chickens have emerged from the shell, the inte- 
rior of the cask should be carefully cleaned, and an artificial 
''mother" placed inside. This last consists of a loosely-fittincr 
disk of wood, covered on its under side with sheepskin or a piece 
of buffalo-robe. Under it the chickens nestle. It may be sup- 
ported from the head by a piece of cord, or by a rod held in 
clamps, so that its distance from the bottom of the cask may be 



238 HOUSEHOLD HINTS. 

adjusted to suit. The warmth necessary for the young chickens 
is maintained by the manure, so that the latter answers both for 
this purpose and for the hatching. The slide mentioned above, 
as located in the head of the cask, is intended for ventilating the 
interior. 

This plan is now in practical operation on one of the largest 
poultry farms in the country and is evidently more simple than 
any other involving the use of special apparatus and gas or lamps 
for heating. A cylindrical vessel must be used — never a square 
one, since the chickens, in the latter case, will crowd into corners 
and smother each other. The number of eggs hatched depends 
upon the size of the cask or the number of casks used. As many 
as one thousand eggs have been thus incubated at a time. Any 
farmer having a manure-heap, however small, can easily test the 
plan, if only with a dozen eggs. The matter requiring the 
greatest care is to keep the temperature in the cask uniform, and 
to have the manure sheltered from rain, which would cool it. 

Ink, Indelible, To remove. — If the ink is a nitrate of silver 
preparation, it may be taken out of the fabric (1) by washing the 
latter in a solution of hyposulphite of soda, or (2) by moistening 
it with a solution of bichloride of copper, and then washing it 
with liquid ammonia. 

Ink-Stains, To remove, from mahogany. — Put a few drops of 
spirits of nitre in a teaspoonf ul of water, touch the spot with a fea- 
ther dipped in the mixture, and, on the ink disappearing, rub it 
over immediately 'with a rag wetted in cold water, or there will 
be a white mark which will not easily be effaced. 

Ink- Stains, To remove. — Wash carefully with pure water, and 
apply oxalic acid ; and, if the latter changes the dye to a red 
tinge, restore the color by ammonia. 

Insect Bites. — A good remedy is borax, 1 oz., dissolved in 1 
pint water previously boiled and allowed to cool. 

Keys, Fitting, — When it is not convenient to take a lock apart 
to fit a new key, the key-blank should be smoked over a candle, 
inserted in the keyhole, and pressed firmly against the opposing 
wards of the lock. The indentations in the smoked portion made 
by the wards will show where to file. 

Lamp-Burners, To fasten kerosene. — Plaster of Paris mixed 
with resin soap is a good cement for this purpose. 

Lead-Colic, Preventives of. — If working in lead, wash tlie 
hands several times a day in a strong decoction of oak -bark. 
Keep the hair short, and (if a painter) wear a clean cloth cap. 
The clothes should be frequently washed, and the hands also, es- 
pecially before touching food. Before eating, the mouth should 
be rinsed with cold water. A weak oak bark decoction should be 
used as a wash several times a week. The body should be sponged 
night and morning with cold or tepid water, and the hair tho- 
roughly washed every evening after work. The food should con- 
tain a large proportion of fatty substances, and milk should be 
taken in large quantities. 

Leaf and Flower Impressions, To make. — Take a small 
quantity of printer's ink, thinly put it on glass, evenly distribut- 



HOUSEHOLD HINTS. 239 

ed. The end of the index-fiDger will serve as the printer's ball, 
to cover one side of the leaf uniformly ; then lay it to the exact 
place where you wish the print to be ; lay over it a piece of thin, 
soft paper large enough to cover it ; then, without moving the 
leaf, press all parts of it with tl>e end of the thumb firmly, and 
you will have a perfect impression, that no engraver can excel ; 
and by adjusting the leaves at the proper points, accurate prints 
can be taken, and, aided with the brush or pen, the stem and 
whole plant can be shown. Excellent specimens of impressions 
of barks of trees can be made by slicing the bark ; and with a 
little care, the stems can also be taken, as well as flowers. When 
colored with the aniline colors, they are very like colored en- 
gravings. 

Leather, To water- proof. — Saturate with castor-oil. This is 
excellent for winter boots. 

Life Preserver, A simple. — It is not generally known that, 
when a person falls into the water, a common felt hat can be 
made use of as a life-preserver. By placing the hat upon the 
water, rim down, with the arm around it pressing it slightly to 
the breast, it will bear a man up for hours. 

Linen, To bleach. — Javelle water, used for turning white the 
dirtiest linen and removing stains, is composed of bicarbonate of 
soda, 4 lbs. ; chloride of lime, 1 lb. Put the soda into a kettle over 
the fire, add 1 gallon of boiling water, let it boil from ten to fif- 
teen minutes, then stir in the chloride of lime, avoiding lumps. 
Use when cool. This is good for removing fruit-stains from 
white underwear. 

Marble, To clean. — Common soda, 2 parts ; pumice-stone (pul- 
verized), 1; finely powdered chalk, 1. Sift through a fine sieve, 
and mix with water. Rub all over the marble until the stains 
are removed. Then wash the stone with soap and water. Marble 
that is yellow with age, or covered with green fungoid patches, 
may be rendered white by first washing it with a solution of per- 
manganate of potash of moderate strength, and while yet moist 
with this solution, rubbing with a cloth saturated with oxalic 
acid. As soon as the portion of the stone operated upon becomes 
white, it should be thoroughly washed with pure water to re- 
move all traces of the acid. 

Match-Scratchers. — The best are pieces of shark-skin, or 
squares of fine wire gauze. 

Mice, To kill. — Sprinkle some grain near the holes, and throw 
near by a few bits of cotton saturated in chloroform. This has 
been tested, and mice have been found dead, two or three at a 
time, lying with their noses near the cotton. 

Mildew, To remove. — Make a very weak solution of chloride 
of lime in water (about a heaping teaspoonful to a quart of 
water), strain it carefully, and dip the spot on the garment into 
it ; and if the mildew does not disappear immediately, lay it in 
the sun for a few minutes, or dip it again into the lime-water. 
The work is effectually and speedily done, and the chloride of 
lime neither rots the cloth nor removes delicate colors, when 



240 HOUSEHOLD HINTS. 

sufficiently diluted and the articles rinsed afterward in clear 
water. 

Moss Ornaments. — A beautiful orrament for the sittinor-room 
can be made by covering a common glass tumbler with moss, the 
latter fastened in place by sewing-cotton wound around. Then 
glue dried moss upon a saucer, into which set the tumbler, filling 
it and the remaining space in the saucer with loose earth from 
the woods. Plant the former with a variety of ferns, and the 
latter with wood- violets. On the edge of the grass also plant 
some of the nameless little evergreen vine, which bears red 
(scarlet) berries, and w^hose dark, glossy, ivy-like foliage will 
trail over the fresh blue and white oi the violets with beautiful 
effect. Another good plan is to fill a rather deep plate with some 
ot the nameless but beautiful silvery and light green and delicate 
pink, mosses, which are met with in profusion in all the swamps 
and marshes. This can be kept fresh and beautiful as long as it 
is not neglected to water it profusely once a day. It must, of 
course, be placed in the shade, or the moss will blanch and die. 
In the Centre of this, a clump of large azure violets should be 
placed, adding some curious lichens and pretty fungous growth 
from the barks of forest-trees, and a few cones, shells, and 
pebbles. 

Mosquitoes, To drive oft*. — Rub the skin with essence of penny- 
royal, or with a little coal-oil on a bit of cotton. The smell of 
the oil disappears in a few minutes. 

Mustard Poultice, To make a. — In making a mustard plaster 
use no water, but mix the mustard with white of egg, and the 
result will be a plaster which will draw perfectly, but will not 
produce a blister, no matter how long it is allowed to remain. 

Mucilage, Pocket. — Boil 1 lb. best white glue, and strain very 
clear ; boil also 4 oz. isinglass, and mix the two together ; place 
them in a water-bath (glue-kettle) with i lb. white sugar, and 
evaporate till the liquid is quite thick, when it is to be poured 
into moulds, dried, and cut into pieces of convenient size. This 
immediately dissolves in water, and fastens paper very firmly. 

Newspaper Binder, Temporary. — Take two pieces of light 
wire, strong enough to reach across the paper once, and three or 
four pieces of stout thread. Place one wire under the paper as 
far from the edge as you choose to bind it. Put the threads 
around the lower wire up through the paper, and tie them over 
the other wire on top. Temporary covers of stiff pasteboard may 
be added, having holes for the reception of the thread, the wires 
being placed on the outside of the cover. The successive papers 
are, of course, to be threaded, one by one, by means of an awl or 
coarse needle. 

Oil-Cloths, Cleaning. — These should not be washed with 
soap. A coat of good copal varnish at long intervals improves 
them. Oil-cloths should never be scrubbed. Wipe with a wet 
cloth, after brushing with a soft floor- brush. 

Oiled Floors. — The scrapings from these should immediately 
be |)laced in the open air. They are liable to spontaneous com- 
bustion. 



HOUSEHOLD HINTS 241 

Oil-Paintings, To restore old.— Take the painting out of the 
frame, lay it on a table, face up, and keep a wet cloth on it for 
two or three days, changing or cleaning the cloth as often as it 
becomes soiled. When the painting is clean, wash it with a 
sponge or brush dipped in nut-oil. This is much better than 
varnishing 

Painter's Colic. — (1.) One drachm of sulphuric acid in 10 
pints of table or spruce beer, or mild ale. Shake well, and allow 
it to stand for a few hours. Take a tumblerful twice or three 
times daily. (2.) Make a beer of molasses, 14 lbs. ; bruised gin- 
ger, ^ lb.; coriander-seed, ^ oz.; capsicum and cloves, J oz. each ; 
water, 12| galls.; yeast, 1 pint. Put the yeast in last, and let it 
ferment. When the fermentation has nearly ceased, add sul- 
phuric acid, 1^ ozs., mixed with 12 ozs. water, and 1| ozs. bicar- 
bonate of soda dissolved in water. It will be fit to drink in three 
or four days. 

Paint, To clean. — Dip a flannel rag into warm water, and wring 
it out nearly dry. Take up on the rag as much whiting as will 
adhere, and rub this on the paint until the dirt or grease disap- 
pears. Wash the part well with clean water, and rub dry with 
soft chamois-skin. 

Paint, To remove, from clothes. — Chloroform will remove 
paint from a garment or elsewhere, when benzole or bisulphide 
of carbon fails. 

Paint, To remove old. — Slake 3 lbs. of stone quicklime in 
water, and add 1 lb. American pearlash, making the whole into 
the consistence of paint. Lay over the old work with a brush, 
and let it remain for from 12 to 14 hours, when the paint is easily 
scraped off. 

Papeh Comfobters. — Two thicknesses of paper are better than 
a pair of blankets, and much lighter for those who dislike heavy 
bedclothes. A spread made of double layers of paper tacked to- 
gether, between a covering of chintz or calico, is really a de- 
sirable household article. Soft paper is the best, but newspapers 
will answer. 

Papering Walls. — Papering and painting are best done in . 
cold weather, especially the latter, for the wood absorbs the oil 
of paint much more than in warm weather ; while in cold 
weather the oil hardens on the outside, making a coat which 
will protect the wood instead of soaking into it. Never paper a 
wall over old paper and paste. Always scrape down thoroughly. 
Old paper can be got off by damping with saleratus and water. 
Then go over all the cracks of the wall with plaster of Paris, 
and, finally, put on a wash of a weak solution of carbolic acid. 
The best paste is made out of rye-fiour, with 2 ozs. glue dissolved 
in 1 qt. paste ; ^ oz. powdered borax improves the mixture. 

Paste, A superior tiour. — Thoroughly mix good clean flour 
with cold water to a paste, then add boiling water, stirring up 
well until it is of a consistence capable of being easily spread 
with a brush. Add to this a little brown sugar, a little corrosive 
sublimate, and about half a dozen drops of oil of lavender; 
and keep, if convenient, two days before using. 



242 



HOUSEHOLD HINTS. 



Petroleum Barrels. — These should not be used to store food 
or drink in. They are poisonous even after being cleaned. 

Plant-Case, A housetop or window. — A fernery or plant-case 
might be arranged to run the whole length of the front windows 
of a story, and be heated by a small boiler placed behind a fire- 




SECTION OF PLANT-CASE. 



place. From this a 2-inch flow and return pipe is taken 
through the case, so as to heat it when required. The space 
around the pipes can be filled with bark, or water if desirable, 
so as to produce a moist and genial bottom heat. The ferns, 
mosses, and other decorative plants, are arranged in flat square 
pans of zinc or earthenware, as shown in our sectional sketch, 
and the effect of the whole, especially when seen from within, 
is very effective, and affords relief to the eye, which might 
otherwise look out on a dismal prospect of blackened roofs and 
soot-be fj-rimed chimney -pots. 

Plants, Window, Care of. — Plants kept in the windows 
should be turned every morning, or the light, striking on one 
side only, will draw the plant to that side, so that all its branches 
and leaves will turn toward the window. The water in the 
saucers should never be applied to the plants. In cuttinof slips 



HOUSEHOLD HINTS. 243 

of any plant, always choose tlie youngest branches ; and cut off 
the slip at the junction of a joint or leaf, since the roots shoot 
more readily from such joints, if you follow these directions, and 
put sufficient sulphate of ammonia to just taint the water applied 
to your plants, you may cultivate with success almost any plant, 
even though you are an entire novice. 

Plant- Cases, Waedian, Management of. — The following prin- 
ciples are those upon which a fern-case should be constructed : 
1. Have no apparatus or arrangement for drainage. 2. Make 
your case as air-tight as possible, allowing for no ventilation. 

Ferns require, tor their growth, shade and moisture ; upon the 
former, in a great degree, depends the latter. A northern or 
eastern aspect, where the morning sun reaches the case, we think 
is best. As regards moisture, we have the principle of self-sup- 
port in an air-tight case ; for if you allow the sun to reach the 
case for an hour or so in the morning, you will find that the 
moisture needful for the growth of your ferns is extracted from 
the earth ; and when evening comes, this same moisture will 
condense and fall. Each day, this process of extraction and con- 
densation takes place, and your plants flourish under a necessary 
and sufficient moisture. Now, this being the kind of air we 
want, we must not, of course, ventilate our case, and allow it to 
escape, otherwise the dry air of our rooms would enter, and the 
watering of the case become a necessity. This at once upsets all 
the benefits derived from these cases. The temperature, also, 
must be much more even in an air-tight case than in a ventilated 
one, where the constant opening and shutting of doors and win- 
dows would affect it. If we have no watering to do, w^e have no 
w^ater to run off", and consequently require no drainage in the bot- 
tom of our case. Now, in this air-tight principle, we get at the 
secret. 

In stocking Wardian cases, the amateur will find that almost 
all ferns and mosses will do well in this case. T?here ^re few of 
our greenhouse ferns that will not do well under this treatment ; 
the gold and silver ferns are perhaps the exception ; they do not 
always attain their full size and beauty in a Wardian case, but 
the adiantnms, pteris, polypodiums, blechnums, and others do 
well. 

In planting a case, do not place the plants too near, ncr use 
too many of a large size, but put in a few plants and of a mode- 
rate size. Water well after setting the plants out, and shade the 
case for a day or two ; then give it the morning sun each day 
for an hour or two, and your ferns will soon start. Nothing can 
be more interesting than to watch them — the frond pushes its 
head above the earth, the heat and moisture of the case have 
their effect, and it gradually rises and uncurls till it reaches its 
height, then it expands into the most beautiful and graceful of 
shapes ; then what can exceed in delicacy and freshness this 
newly-born part ? The lycopodiums grow finely, and spread very 
rapidly in the case ; small pieces introduced at regular intervals in 
the case will, in a marvelously short time, double their original size ; 
and if the pendent roots of the creeping species are pressed well on 
to the surface of the earth, the spaces between the plants and ferns 
will soon be filled up, and a rich and delicate carpet be produced 



244 



HOUSEHOLD HINTS. 



over the whole case. For climbers, nothing can give more satis- 
faction thaii ficus sHpulata, which can be obtained at all green- 
houses. The roots of this plant, which strike out at every joint, 




THE PRINCESS OF WALES CASE. 



have an adhesive power, and will attach themselves firmly to the 
glass in the case, which renders the growth more rapid and regu- 
lar. It is a very interesting plant to watch ; the roots adhering 
to the glass allow a free use of the microscope, and the orrowth 
and circulation can be studied to great advantage from the out- 
side of the case. 




THE SYDENHAM CASE. 



As to soil, the best mixture for the growth of ferns and 
lycopodiums is the following : Leaf- mould, 2 parts ; fresh 
sand, 1 part ; gravel, about the size of a pea, 1 part ; and 
stable manure, chopped very fine, 1 part. Ferns which grow na- 
turally in dry places can be arranged on rock-work in the centre 



HOUSEHOLD HINTS. 245 



of the case, if it is large enough to admit of it, and those re- 
quiring more moisture should be placed nearer the sides of the 
case, and they will get more moisture from the glass, where it 
deposits in grer.t quantities. The spores of ferns can be sown on 
the surface of the earth in the Wardian case, and a constant sup- 
ply of young plants can in this way be obtained, thus enabling 
the student to watch them in every stage of development. 

It happens that not unfrequently the larvae of insects are in- 
troduced in the earth into the case, and hatch out under the in- 
fluence of the heat. To provide against this, it will be found 
useful and interesting to put in a small-sized toad, and insects 
will disappear very soon, and give no further trouble. Toads 
will live through the winter perfectly well in this way, and their 
habits can be studied ; some may become aware, by trying this 
experiment, that the toad, although not one of the handsomest of 
our reptiles, is not the least interesting. 

Plants, Potting. — Those who find their efforts to raise house- 
plants frustrated by worms may be able to win success by boiling 
the earth before setting the plants. Use little water, and allow 
it to simmer away after a few minutes of hard boil. 

Polish, Furniture. -^Shave very fine white wax, 3 ozs., cas- 
tile-soap, 1 oz. ; put the wax in 1 gill turpentine, and let it stand 
24 hours. Boil the soap in 1 gill water, and add to wax and tur- 
pentine. 

Potatoes, Saratoga, Fried. — The following is all there is of 
the cook's secret for producing those world-renowned potatoes 
served at Moon's Lake House, Saratoga Springs, every summer : 
Peel good-sized potatoes, and slice them as evenly as possible ; 
drop them into ice-water. Have a kettle of lard, as for fried 
cakes, and very hot. Put a few at a time into a towel, shake 
them about to dry them, and then drop into the hot lard. Stir 
them occasionally ; and when of a light brown, take them out 
with a skimmer. If properly done, they will not be at all greasy, 
but crisp without, and mealy within. 

Potatoes, Frozen. — These can be cured by soaking in water 3 
days before cooking. 

Rust-Spots, To remove from cloth. — Wet the spots of iron- 
rust on muslin or white dress-goods thoroughly with lemon-juice, 
then lay in the hot sun to dry. Repeat the same if the color is 
not removed by one application. When dry, rinse in clear, cold 
water. Lemon-juice can not be used on colored goods, as it will 
take out printed colors as well as stains. It will remove all kinds 
of stains from white goods. 

Ring, To remove, when tight on the finger. — In case a finger- 
ring becomes too tight to pass the joint of the finger, the finger 
should first be held in cold water to reduce any swelling or inflam- 
mation. Then wrap a rag soaked in hot water around the ring to 
expand the metal, and lastly soap the finger. A needle threaded 
with strong silk can then be passed between the ring and finger, 
and a person holding the two ends and pulling the silk, while 
sliding it around the periphery of the ring, will readily remove 
the latter. Another method is to pass a piece of sewing-silk un- 



246 HOUSEHOLD HINTS. 

der tlie ring, and wind the thread in pretty close spirals and close- 
ly around the finger to the end — that below the ring — and begin 
unwinding. 

Rice, To boil. — The way they boil rice in India is as follows : 
Into a saucepan of 2 quarts water, when boiling, throw a table- 
spoonful of salt ; then put in 1 pint rice, previously well washed 
in cold water. Let it boil 20 minutes, throw out in a colander, 
drain, and put back in the saucepan, which should be stood near 
the fire for several minutes. 

Rain- Water, To preserve sweet. — A drachm of pounded alum 
to a gallon of water is suflBcient. After 24 hours, the water will 
be cleansed. All wooden vessels to hold water should be cliarred 
inside. If a mixture in the proportion of i lb. of lime, made into 
a paste, and added to a spoonful of powdered alum, be put into 200 
gallons of water, it will soften the water, and precipitate vegeta- 
ble and other matter. 

Rats, Bait for. — Put a drop of rhodium oil on a bit of cheese or 
meat. These animals detest chloride of lime and coal-tar. 

Rats, To catch. — Cover a common barrel with stiff paj.^er, tying 
the edge around the barrel. Place a board so that the rats can 
have easy access to the top. Sprinkle cheese or other bait on the 
paper, and allow the rats to eat there unmolested for several days. 
Then place in the bottom of the barrel a stone 6 or 7 inches high, 
and pour in w^ater until all the stone is covered, except for a space 
about big enough for one rat to craw4 upon. Now replace the 
paper, first cutting a cross in the middle. The first rat that 
climbs on the barrel-top goes through into the water, and 
climbs on the stone. The paper comes back to its original posi- 
tion, and the second rat follows the first. Then begins a fight 
for the possession of the dry place on the stone, the noise of which 
attracts the others, who share the same fate. 

Razors, Paper for sharpening. — By merely wiping the razor on 
the paper to remove the lather after shaving, a keen edge is main- 
tained without further trouble. The razor must be well sharpen- 
ed at the outset. First, procure oxide of iron (by the addition of 
carbonate of soda to a solution of persulphate of iron), well wash 
the precipitate, and finally leave it of the consistence of cream. 
Spread this over soft paper very thinly with a soft brush. Cut 
the paper in pieces two inches square, dry, and it is ready for 
use. 

Razor-Strop, To make a. — Select a piece of satin, maple, or 
rose wood, 12 inches long, If inches wide, and f inch thick ; allow 
3| inches for length of handle. Half an inch from where the 
handle begins, notch out the thickness of the leather so as to 
make it flush toward the end. Taper also the thickness of the 
leather ; this precaution prevents the case from tearing up the 
leather in putting the strop in. Then round the wood very 
slightly, just enough (say -fV oi an inch) to keep from cutting by 
the razor in stropping and turning over the same. Now select a 
proper-sized piece of fine French bookbinder's calfskin, cover with 
good wheat or rye paste, then lay the edge in the notch, and se 
cure it in place with a small vise, proceed to rub it down firmly 



HOUSEHOLD HINTS. 247 

and as solid as possible witli a tooth-brush handle (always at hand, 
or should be), and, after the whole is thoroughly dry, trim it neat- 
ly and make the case. 

Sleeplessness, Cure for. — Mr. Frank Buckland says : " If I am 
much pressed with work, and feel I shall not sleep, I eat two or 
three small onions, and the effect is magical. Onions are also 
excellent things to eat when much exposed to intense cold. In 
salmon-fishing, common raw onions enable men to bear the ice 
and cold of the semi-frozen water much better than spirits, beer, 
etc. If a person can not sleep, it is because the blood is in his 
brain, not in his stomach ; the remedy, therefore, is obvious : call 
the blood down from the 'brain to the stomach. This is to be 
done by eating a biscuit, a hard-boiled eo^g, a bit of bread and 
cheese, or something. Follow this up with a glass of wine or 
milk, or even water, and you will fall asleep." 

Smoked Meat, To preserve. — The keeping qualities of smoked 
meat do not depend upon the amount of smoking, but upon the 
uniform and proper drying of the meat. It is of considerable ad- 
vantage also to roll the meat on its removal from the salt, before 
smoking, in sawdust or bran. By this means the crust formed in 
smoking will not be so thick ; and if moisture condenses upon 
the meat it remains in the bran, the brown coloring matter of the 
smoke not penetrating. The best place to keep the meat is in a 
smoke-house, in which it remains dry without drying out entirely, 
as it does when hung in a chimney. 

Spatter- Work Pictures. — These are delicate designs in white 
appearing upon a softly-shaded ground. Procure a sheet of fine 
uncalendered drawing-paper, and arrange thereon a bouquet of 
pressed leaves, trailing vines, letters, or any design which it is de- 
sired to have appear in white. Fasten the articles by pins stuck 
into the smooth surface, which should be underneath the paper. 
Then slightly wet the bristles of a tooth or other brush in rubbed 
Indian ink, or in common black writing-ink, and draw them across 
a stick in such a manner that the bristles will be bent and 
then quickly released. This will cause a fine spatter of ink upon 
the paper. Continue the spattering over all the leaves, pins, 
and paper, allowing the centre of the pattern to receive the 
most ink, the edges shading off. When done, remove the design, 
and the forms will be found reproduced with accuracy on the 
tinted ground. With a rustic wooden frame, this forms a very 
cheap and pretty ornament. 

Spoons, To remove stains on, caused by boiled eggs. — Rub 
with common salt. 

Sponges, Cleaning. — A gelatinous substance frequently forms 
in sponges after prolonged use in water. A weak solution of 
permanganate of potassa will remove it. The brown stain caused 
by the chemical can be got rid of by soaking in very dilute muria- 
tic acid. An old and dirty sponge may be cleaned by first soak- 
ing it for some hours in a solution of permanganate of potassa, 
then squeezing it, and putting it into a weak solution of hydro- 
chloric acid, 1 part acid to 10 parts water. 



248 HOUSEHOLD HINTS. 

Sponges, To bleach. — Wash first in weak muriatic acid, then 
in cold water ; soak in weak sulphuric acid, wash in water again, 
and finally rinse in rose-water. 

Stains op Acid Fruit, To remove, from the hands. — Wash 
the hands in clear water, wipe them lightly, and while they are 
yet moist, strike a match and shut your hands around it so as to 
catch the smoke, and the stain will disappear. 

Starch, To prevent souring when boiled. — Add a little sul- 
phate of copper. 

Stone, To remove moss from. — This is useful for the greea 
mould which forms on marble and brown-stone steps. Apply a 
solution of 75 grains of carbolic acid to 1 quart of water. 

Stoppers, Glass, To remove. — To move a tight glass stopper, 
hold the neck of the bottle to a flame, or take two turns of a string 
and seesaw it. The heat engendered expands the neck of the 
bottle before the expansion reaches the stopper. 

Stove-Holes in Walls.— See that these openings for the 
pipes are protected by good tin covers after the stoves are taken 
down. Do not stuff rags in. 

Straw Matting, Washing, — Use a cloth dampened in salt 
water. Indian meal sprinkled over it and thoroughly swept out 
will also^cleanse it finely. 

Styptic Paper, for stopping the bleeding of small wounds. — 
Mix gum benzoin (best quality), 1 lb.; rock alum, 1 lb.; water, 4-^ 
gals. Boil in a tin vessel for 4 hours, replacing the water lost by 
evaporation. Saturate paper with the solution, dry carefully, and 
brush over with a concentrated solution of perchloride of iron. 
Keep in a water-proof and air-tight case. 

Safe, Home-made fire-proof. — The best is a hole in the ground 
well lined wiili brick and cement. 

Shirt-Bosoms, Glossing, — Take 2 ozs. of fine white gum-ara- 
bic powder, put it in a pitcher, and pour on a pint or more of wa- 
ter, and then, having covered it, let it stand all night. In the 
morning, pour it carefully from the dregs into a clean bottle, cork, 
and keep it for use. A teaspoonful of gum-water stirred in a 
pint of starch, made in the usual way, will give to lawns, white 
or printed, a look of newness when nothing else can restore them, 
after they have been washed. 

Shoes, Bronzing. — Black shoes may be bronzed by a strong 
solution of aniline red in alcohol. 

Shoes, Black varnish for. — Take 10 parts, by weight, of shellac, 
and 5 of turpentine. Dissolve in 40 parts alcohol, in which fluid 
should be previously dissolved 1 part extract of logwood, with 
some neutral chromate of potassa and sulphate of indigo. This 
varnish is to be kept in well-stoppered bottles. 

Sidewalks, Slippery. — Put on hard sand instead of ashes. 

Silk, Washing. — The way to wash silk is to spread it smooth- 
ly upon a clean board, rub white soap upon it, and brush it with 
a clean hand- brush. 

Silver, To clean. — A strong solution of hyposulphite of soda is 
useful for this purpose. 



HOUSEHOLD HINTS. 249 

Silk, etc., To clean. — A teaspoonful of powdered borax dis- 
solved in 1 qt. tepid water is good for cleaning old black dresses 
of silk, cashmere, or alpaca. 

Silver-Plate, To keep bright. — Warm the articles, and coat 
carefully over with thin collodion diluted with alcohol, using a 
wide soft brush for the purpose. 

Sink- Spouts, To thaw frozen. — Place one end of a piece of lead 
pipe against the ice to be thawed, and then through a funnel in 
the upper end pour boiling water. Keep the pipe constantly 
against the ice, and a foot or more per minute can be penetrated. 
In order to thaw out water-pipes that become frozen and are inac- 
cessible, the plan used by New-York plumbers is to surround 
small india-rubber tubing with coiled wire so as to stiffen it and 
admit of ita being inserted far into the pipe. Through the tube a 
current of steam from a small boiler over a charcoal furnace is 
allowed to pass. This acts very quickly, except when the pipe 
takes a very irregular course, in which case there is no remedy ex- 
cept to dig down into the earth or break out walls until the pipe 
can be reached, and thawed by the direct application of heat. 

Soap, Adulteration of, by starch.— This is detected by dissolv- 
ing the soap in alcohol, which leaves the starch behind. 

Soap, Gall, To make. — Gall soap, excellent for washing silks 
and ribbons, may be made by heating 1 lb. cocoanut-oil to 60° 
Fahr., into which -I- lb. caustic soda is gradually stirred. To this 
i lb. Venice turpentine, previously warmed in another vessel, is 
added. The kettle is allowed to stand for four hours, subject to 
a gentle heat, after which the fire is increased until the contents 
are perfectly clear. One pound ox-gall, followed by 2 lbs. castile- 
soap, is then mixed in, and the whole allowed to cool, when it 
may be cut into cakes. 

Soap, Habd, To prevent crumbling. — Dip the bars in a mixture 
of resin-soap, beef -tallow, and wax. 

Soap, Home-made. — Soap-making is not an easy process ; some- 
times the ashes are poor, or the right proportions of lye and 
grease are not used ; at other times the soap appears to be good 
when put up, but changes entirely after standing a few days. 
The last trouble usually arises from getting the soap too strong 
and diluting with water. If very strong, it will be thin and dark ; 
and by adding cold water and thoroughly stirring, the color is 
chaaged many shades lighter and the mass thickened, giving it 
the appearance of a No. 1 article, while in reality it is very poor. 
Hickory-ashes are the best for soap-making, but those from sound 
beach, maple, or almost any kind of hard wood except oak, will 
answer well. A common barrel, set upon an inclined platform, 
makes a very good leach ; but one made of boards set in a 
trough in V- shape is better, for the strength of the ashes is better 
obtained, and it may be taken to pieces when not in use, and put 
away. First, in the bottom of the leach, put a few sticks ; over 
them spread a piece of carpet or woolen cloth, which is much 
better than straw ; put on a few inches of ashes, and then from 4 
to 8 qts. lime ; fill with moistened ashes, and pack well down. 
Pack the finest in the centre. It is difficult to obtain the full 
strength of ashes in a barrel without removing them after a day's 



250 HOUSEHOLD HIXTS. 

leaching, and mixing them up and replacing. The top should be 
first thrown off and new ashes added to make up the proper quan- 
tity. Use boiling ^vater for second leaching. Take about 4 gal- 
lons lye, and boil up thoroughly with 12 lbs. clear grease, then 
add the lye as it is obtained, keeping a slow fire and stirring often 
until you have a barrel of soap. After boiling the grease and 4 
gallons lye together, it may be put in a barrel and the rest of the 
lye added there. This will form good soap if frequently stirred ; 
but the heating process is the best, when weather and time will 
permit. 

Tattoo-Marks on the Skin, To remove. — Blister the part with 
a plaster a little larger than the mark ; then keep the place open 
for a week with an ohitment ; finally, dress it to get well. As the 
new skin grows, the tattoo-marks will disappear. 

Tar- Spots, To remove. — Butter will remove tar-spots. Soap 
and water will afterward take out the grease-stain. 

Tea-Kettle, To prevent rust forming inside a. — Keep an oyster- 
shell in the bottom of the kettle ; and when water is wanted, 
pour off without agitating the vessel. Be careful also not to let 
the water stand in the vessel when not in use. 

Teeth, Extracting, Simple method of, for children. — The ope- 
ration consists in simply slipping a rubber ring over the tooth and 
forcing it gently under the edge of the gum. The patient is 
then dismissed, and told not to remove the appendage, which in a 
few days loosens the tooth, and causes it to fall out. 

Tin, Scouring. — Kerosene and powdered lime, whiting, or wood- 
ashes, will scour tins with the least labor. 

Toothache. — Saturate a bit of cotton wool in a strong solution 
of ammonia, and apply it immediately to the affected tooth. 

Tubs and Pails, to prevent shrinking of. — Saturate with gly- 
cerine. 

Vegetables, To wash. — Vegetables should never be washed 
until immediately before prepared for the table. Lettuce is made 
almost worthless in flavor by dipping it in water some hours be- 
fore it is served. Potatoes suffer even more than other vegetables 
through the washing process. They should not be put in water 
till just ready for boiling. 

Ventilation of Sleeping-Rooms, Simple plan for. — A piece 
of wood 8 in. high, and exactly as long as the breadth of the 
window, is to be prepared. Let the sash be now raised, the slip 
of wood placed on the sill, and the sash drawn closely upon it. 
If the slip has been well fitted, there will be no draft in conse- 
quence of this displacement of the sash at its lower part ; but the 
top of the lower sash will overlap the bottom of the upper one, 
and between the two bars perpendicular currents of air, not felt 
as draft, will enter and leave the room. 

Vinegar, To make, from molasses. — Vinegar may be made by 
mixino- 16 parts pure water, 1 part syrup of molasses, and 1 part 
baker's yeast at a temperature of about 80° Falir., and keeping the 
compound in a warm atmosphere from ten to thirty days. A 
little old vinegar, added on the second or third day, will aid the 
process. 



HOUSEHOLD HINTS. 251 

Vinegar, Raspberry. — Pour over 1 lb. bruised berries, 1 qt. of 
the best cider vinegar ; next day, strain the liquor on 1 lb. of fresh 
ripe raspberries, bruise them also, and on the following day do 
the same. Do not squeeze the fruit, only drain the liquor 
thoroughly. Put the juice into a stone jar, and add sugar in pro- 
portion of 1 lb. to a pint. When the sugar is melted, place the 
jars in a saucepan of water, which heat ; skim the liquor, and 
after it has simmered for a few minutes, remove from the fire, 
cover, and bottle. 

Washing-Blue. — Twenty lbs. white potato starch, 20 lbs. 
wheat starch, 20 lbs. Prussian blue, 2 lbs. indigo carmine, and 2 lbs. 
finely-ground gum-arabic are mixed in a trough, with the gradual 
addition of sufficient water to form a half-fluid, homogeneous 
mass, which is then poured out on a board with strips tacked to 
the edges. It is then allowed to dry in a heated room until it 
does not run together again when cut. It is next cat, by a 
suitable cutter, into little cubes, and allowed to dry perfectly. 
They are finished by being placed in a revolving drum, with a 
suitable quantity of dry and finely pulverized Paris blue, until 
they have a handsome appearance. The cost is about 12 cents 
per pound. 

Washing Colored Fabrics. — Before washing almost any 
colored fabrics, soak them in water, to each gallon of which a 
spoonful of ox-gall has been added. A teacupf ul of lye in a pail 
of water is said to improve the color of black goods. A strong 
tea of common hay will improve the color of French linens. 
Vinegar in the rinsing water, for pink and green, will brighten 
those colors ; and soda answers the same end for both purple 
and blue. 

Wall-Paper, Removing stains on.. — Stains on wall-paper can 
be cut out with a sharp penknife, and a piece of paper so nicely 
inserted that no one can see the patch. 

Warts, Cure for. — Rubbing warts, night and morning, with a 
moistened piece of muriate of ammonia is said to cause their 
disappearance without pain or a scar resulting. 

Water-Closets, Ventilating pipes for. — Extend pipes from 
water-closet traps, or one (larger) from the main waste-pipe, into 
the nearest chimneys. The pestilent gases will thus be carried 
off instead of being allowed to escape into the house. 

Water-Pipes, To prevent freezing of.— Have a cock in the 
cellar by which the water can be turned off from the house. 

Water, To purify, from smoke. — Enough permanganate of 
potassa is added to give the faintest possible tinge to the water. 
After standing 24 hours, the impurities will all be precipitated. 

Wounds, Cut. — A wound made by a knife or other sharp in- 
strument is best healed by bringing the edges together and put- 
ting on a bandage which will not exclude the air. Nature will 
work the cure, if the person be healthy, much better than any 
salve or ointment. 

Water-Lilies, To raise. — Water-lilies may be raised about 
one's house by the following method : Sink in the ground the 
half of an old cask, and cover the bottom with peat and swamp 



252 HOUSEHOLD HINTS. 

mud, and then fill with water. Dig the lily roots early in the 
spring, and place them in the earth at the bottom of the tub. 

Windows, Washing. — In washing windows, a narrow-bladed 
wooden knite, sharply pointed, will take out the dust that hardens 
in the corners of the sash. Dry whiting will polish the glass, 
which should first be washed with weak black tea mixed with a 
httle alcohol. Save the tea-leaves for the purpose. 

Wine, Preservation of, by heating. — Wine may be kept with- 
out altering in quality for an indefinite period of time, in all 
climates, after having been first submitted to the action of artifi- 
cial heat. The temperature to which it must be raised is from 
131° to 140° Fahr. If the wine does not contain naturally more 
than 10 or 12 per cent of alcohol, it is best to add 1| per cent 
more before the shipping of it. The wine is to be heated by 
steam and artificially cooled. 

Yeast, Compressed. — Previously malted barley and rye are 
ground up and mixed, next put into water at a temperature of 
65° to 75° ; after a few hours the saccharine liquid is decanted 
from the dregs, and the clear liquid brought into a state of fer- 
mentation by the aid of some yeast. The fermentation becomes 
very strong ; and by the force of the carbonic acid which is 
evolved, the yeast globules are carried to the surface of the 
liquid, and, forming a thick scum, are removed by a skimmer, 
then placed on cloth filters, drained, washed with a little distilled 
water, and next pressed into any desired shape by means of 
hydraulic pressure, and covered with a strong and well-woven 
canvas. It keeps from 8 to 14 days, according to the season, and 
is excellent. 

Yeast for Hot Climates. — Boil 2 ozs. best hops in 4 qts. water 
for Y hour ; strain and cool to new-milk warmth. Put in ^ lb. 
sugar, 1 tablespoonful of salt ; beat up 1 lb. of the best flour with 
some of the liquor, and mix all well together. Let it stand for 3 
days, and on the third day add 3 lbs. mashed and boiled pota- 
toes. On the next day, strain, and it is ready for use. This will 
keep for 2 or 3 months in a moderately cool place. The yeast is 
very strong ; half the usual quantity necessary for baking is 
sufficient. 

Yeast, Vienna. — Vienna bread and Vienna beer are said to be 
the best in the world. Both owe their superiority to the yeast 
used, which is prepared in the following manner : Indian corn, 
barley, and rye (all sprouting) are powdered and mixed, and then 
macerated in water at a temperature of from 149° to 167° Fahr. 
Saccharification takes place in a few hours, when the liquor is 
racked off and allowed to clear, and fermentation is set up by the 
help of a minute quantity of any ordinary yeast. Carbonic acid 
is disengaged during the process with so much rapidity that the 
globules of yeast are thrown up by the gas, and remain floating 
on the surface, where they form a thick scum. The latter is 
carefully removed, and constitutes the best and purest yeast, 
which, when drained and compressed in a hydraulic press, can be 
kept from 8 to 15 days, according to the season. 



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